If you are sufficiently randomizing afterwards (I believe you need a minimum of 7 riffle shuffles to achieve a good randomization), then there is no effect of this.
If you are insufficiently randomizing afterwards, to the point where it has an effect, then you are cheating already by insufficiently randomizing.
Parinoid has invented a term "represents", as used in the phrase "some configurations more closely resemble (or represent, if you'd prefer) a randomized deck than others." This term is not used in mathematics when discussing random numbers, and this poster has not provided a rigorous definition of it, so it would be dangerous to give it any weight until one is provided.
Furthermore, parinoid has claimed that it is unreasonable to truly randomize a deck in a timely manner, and accepts some lesser amount of shuffling as sufficiently random. However, as has been quoted in this thread, the rules require that you not have any information about the relative positions of any cards in the deck. If you have reason to believe that your shuffled deck looks different because of mana-weaving, you have information about the relative positions of cards in the deck.
So according to parinoid's logic, mana-weaving is always cheating, because, supposedly, true randomization is impossible. Unfortunately, according to this logic, it is also cheating to look at your deck, then shuffle and present it, which nearly every player does before nearly every game.
I personally believe that it IS reasonable to expect good shuffling from players that have good skill with their hands, but of course some players are slower shufflers than others. Players physically incapable of randomizing their deck should notify the Head Judge before a tournament starts and accommodations will be made for them if possible, however it is not the judges' responsibility to make such accommodations.
Can't let this die with ignorance having the last word.
What knowledge or information are you claiming I lack?
Parinoid has invented a term "represents", as used in the phrase "some configurations more closely resemble (or represent, if you'd prefer) a randomized deck than others." This term is not used in mathematics when discussing random numbers, and this poster has not provided a rigorous definition of it, so it would be dangerous to give it any weight until one is provided.
It's used all the time in statistics, when considering if a sample accurately describes the population it comes from.
In this case, I'm stating that a deck with the lands interspersed evenly is more representative (ie. is a more typical example or specimen) of a deck that has been randomized through physical manipulation, than a deck where the lands are not interspersed, but all clumped in one section of the deck.
Note that I'm not claiming that it is the best example, just that it is a better one.
Furthermore, parinoid has claimed that it is unreasonable to truly randomize a deck in a timely manner, and accepts some lesser amount of shuffling as sufficiently random. However, as has been quoted in this thread, the rules require that you not have any information about the relative positions of any cards in the deck. If you have reason to believe that your shuffled deck looks different because of mana-weaving, you have information about the relative positions of cards in the deck.
What information do you claim they would have?
Keep in mind that I've been constantly referring to weaving followed by sufficient randomization, which will not maintain the original pattern at all.
It kind of plays into my question, but the premise and conclusion in the third sentence don't follow logically, because you don't state how 'having reason to believe that a shuffled deck looks different because of weaving' results in 'having information about the relative positions of cards in the deck'.
I thought you should know, since you went to the trouble of bolding it and everything.
So according to parinoid's logic, mana-weaving is always cheating, because, supposedly, true randomization is impossible. Unfortunately, according to this logic, it is also cheating to look at your deck, then shuffle and present it, which nearly every player does before nearly every game.
That's quite a leap. I fail to see how you've managed to show that a deck that is not truly random cannot meet the criteria of 'sufficiently random'.
And are you claiming that true randomness is obtainable through physical manipulation?
I personally believe that it IS reasonable to expect good shuffling from players that have good skill with their hands, but of course some players are slower shufflers than others. Players physically incapable of randomizing their deck should notify the Head Judge before a tournament starts and accommodations will be made for them if possible, however it is not the judges' responsibility to make such accommodations.
So, it's been clearly stated by an L2 that the matter is ok. I certainly wouldn't call ignorance on that, unless you yourself happen to be an L3.
A mana weave is a way to set the deck beforehand to simply prevent clumping of cards, and ensure you can get a random shuffle. Then you know nothing will be clumped together once proper randomization begins. If you rifle a deck 7 times after you mana weave, you will not be able to predict what cards will come next. You can make a fairly accurate guess (As to say a few lands and a few not lands) but you should usually be able to say that if your deck has a proper land to not land ratio.
Even if the lands generally stay in a 2-1-2-1 weave ratio, they arent going to be the same lands in that order. So, if the lands aren't the same lands, would you say you still have knowledge of the deck? Here's an example. Say you run 4 sacred foundry (S), 4 blood crypt (B), 4 mutavault (M), and some other basic lands (L). If you mana weave it to look like...
Do you know anything about the deck, besides the fact that every third card will be a land? I don't believe that you can make an accurate statement about it. Though that is in a perfect world, and the weave will not be retained. The weave will be broken, and then shuffled back together, and broken again, and shuffled together, and make it look like...
L-L-4-B-S-3-L-1-M-2-B-M-5-L....
So yes, if you do not shuffle the deck well enough, you are going to end up having knowledge. But the point is random is not real. It's pretty much impossible to get perfect randomization, especially because there are a set number of configurations that the cards can actually sit in. So, all wizards asks is that the deck becomes sufficiently random, and that you can not be sure what card is going to to come next. Even directly after a mana weave, you won't have knowledge of what card will come next, just the general ratio of land to spells. Once the deck is shuffled to change that, and the ratio isn't perfect, then the cards are sufficiently randomized, the deck is shuffled.
IMO, You're more likely to get a sufficiently randomized deck, if you start with everything spaced out somewhat. Because if you have a large group of lands and a large group of spells, and shuffling is certainly not perfect, it's going to be more likely for those like cards to stick together, and come to clumps of those cards. It's statistics. Which is why i always rifle my lands into my deck, and then rifle the deck a few more times before shotgunning for a bit and cutting the deck, then presenting.
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Whats the big deal about black lotus you ask? Well you see, there is no big deal about it. It IS the big deal.
First off, L2's are not gods, they just have a good understanding of the rules and lots of experience judging, as well as running small events. This is a policy question and everyone in this thread has access to the relevant documents. If you still want to give final say to L2's, I should point out that another L2 in this thread has disagreed.
What information do you claim they would have?
Keep in mind that I've been constantly referring to weaving followed by sufficient randomization, which will not maintain the original pattern at all.
It kind of plays into my question, but the premise and conclusion in the third sentence don't follow logically, because you don't state how 'having reason to believe that a shuffled deck looks different because of weaving' results in 'having information about the relative positions of cards in the deck'.
I thought you should know, since you went to the trouble of bolding it and everything.
It's pretty much impossible to get perfect randomization, especially because there are a set number of configurations that the cards can actually sit in. So, all wizards asks is that the deck becomes sufficiently random, and that you can not be sure what card is going to to come next.
These quotations capture what I find to be a problematic understanding of randomization. I am not claiming you can make a deck truly random through physical manipulation. Ask any physicist, and she will say that the only way to do that would be to set up some kind of quantum experiment like a photon reflectivity deal. Everything on a larger scale is deterministic. This is a futile conversation to go down.
In this thread, we define "sufficiently random" as "a state where no player can have any information regarding the order or position of cards in any portion of the deck" (TR 3.9). Here is my understanding of this passage stated as plainly as possible:
Scenario 1:
you mana weave a deck
you shuffle it some number of times
you draw two lands in a row off the top
based on the above steps, you predict the chance of seeing a land (let's say you determine it's 37%, just as an example)
Scenario 2:
you shuffle your deck one hundred times
you draw two lands in a row off the top
based on the above steps, you predict the chance of seeing a land (here, let's say you determine it's 38%)
If these two percentages are different, I believe you have "information regarding the order or position of cards" in the deck. Specifically, you have statistical "information" about how well-distributed ("position") the lands ("cards") are.
Hopefully, shuffling one hundred times is not necessary, but it is the responsibility of each player to shuffle until they have obliterated all statistical knowledge they have about the contents of their deck. If I see someone mana weaving, I can be certain they are either wasting tournament time by doing so, or else they will go on to shuffle few enough times that they have statistical knowledge about the contents of their deck. That's insufficient randomization.
This is all irrelevant. In any game of magic, from casual to Pro Tour, when your opponent shuffles and presents (whether they do it face up in a perfect magic christmas land order or what you consider to be sufficiently randomized [6 shuffles]), you have the opportunity to do the same. In higher RLs, your opponent will always do this. When I first started playing magic, the LGS I went to had a few problems with the mana-weave argument (an argument as old as magic), so players were instructed to shuffle their opponents library at every opportunity.
This boils down to a philisophical question. When you introduce chaos to a system (shuffling your deck), does the amount of order it started with affect the outcome? Like many have said, if mana weave has an outcome, you're not sufficiently randomizing your deck. This is theoretical. If you start shuffling a deck with 24 land on top and 36 spells on bottom, and present after 6 suffles, you will get hosed. In theory, it shouldn't make a difference. To achieve a true state of randomization, we'd have to take into account plenty of other factors. How new are the sleeves, where did the cards start out, do you shuffle top to bottom, top to middle, top to top followed by a pile shuffle.
There's just too many factors to achieve a true randomization. This is why the best bet is to shuffle your opponents deck ALWAYS, even if it is a simple pile shuffle. Sometimes when playing in a new store or a new player, I get dirty looks. I simply explain that shuffling your opponents deck keeps the game honest.
Anyone who is actually offended by shuffling their deck is either cheating, or is offended easily.
you don't state how 'having reason to believe that a shuffled deck looks different because of weaving' results in 'having information about the relative positions of cards in the deck'.
Surely this is true by definition? When I shuffle and present a deck (usually using at least 7 riffles, and a few overhand shuffles, so that the deck is sufficiently shuffled), I know nothing about the order of my deck, and have no reason to believe anything about the distribution.
If you have reason to believe your deck looks different, you have information about the relative position of the cards in it.
Furthermore, this is at odds with your previous statement that weaving followed by sufficient randomization will not maintain that pattern at all, which I agree with. If you weave, and then shuffle enough that the order of the deck is randomized to the point that you have no knowledge about the distribution of cards, such as lands and nonlands, the weave had no effect, either positive or negative. But if you weave, then shuffle, and expect to still have reason to believe that your deck looks different as a result of the weave, then you have not shuffled to the point where the deck "does not maintain that pattern at all".
Weaving and then thoroughly shuffling is a waste of time, but not a violation of tournament procedure, and I'm not going to actively stop anyone from doing it. But believing that it's acceptable to weave and then insufficiently shuffle, as defined by believing your deck still looks different than if you hadn't weaved, is a problem. I want to emphasize that, and the fact that mana weaving will at best raise the suspicions of other players and judges who may well be additionally suspicious of insufficient randomization.
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DCI Level 2 Judge
If your question is "What would a judge do is this situation?", only one person's answer is relevant, and that is the Head Judge at your event. I can quote the rules, but I don't know your HJ.
First off, L2's are not gods, they just have a good understanding of the rules and lots of experience judging, as well as running small events. This is a policy question and everyone in this thread has access to the relevant documents. If you still want to give final say to L2's, I should point out that another L2 in this thread has disagreed.
This exactly. No matter how expert a person is, they can still make mistakes and should not be above reproach.
These quotations capture what I find to be a problematic understanding of randomization. I am not claiming you can make a deck truly random through physical manipulation. Ask any physicist, and she will say that the only way to do that would be to set up some kind of quantum experiment like a photon reflectivity deal. Everything on a larger scale is deterministic. This is a futile conversation to go down.
In this thread, we define "sufficiently random" as "a state where no player can have any information regarding the order or position of cards in any portion of the deck" (TR 3.9). Here is my understanding of this passage stated as plainly as possible:
Scenario 1:
you mana weave a deck
you shuffle it some number of times
you draw two lands in a row off the top
based on the above steps, you predict the chance of seeing a land (let's say you determine it's 37%, just as an example)
Scenario 2:
you shuffle your deck one hundred times
you draw two lands in a row off the top
based on the above steps, you predict the chance of seeing a land (here, let's say you determine it's 38%)
If these two percentages are different, I believe you have "information regarding the order or position of cards" in the deck. Specifically, you have statistical "information" about how well-distributed ("position") the lands ("cards") are.
Hopefully, shuffling one hundred times is not necessary, but it is the responsibility of each player to shuffle until they have obliterated all statistical knowledge they have about the contents of their deck. If I see someone mana weaving, I can be certain they are either wasting tournament time by doing so, or else they will go on to shuffle few enough times that they have statistical knowledge about the contents of their deck. That's insufficient randomization.
You seem to have misunderstood my point.
What I've been trying to say is that the benefit from weaving is that a weaved deck will have less impact on the final result than a fully stacked deck.
That implies that it is harder for one to retain information about the relative position of cards if they weaved first, when compared to if they stacked it in a 20-40 fashion.
I don't understand how one would obtain percentages like what you've used, but in your examples the margin of error in the first example would be much larger than the margin of error in the second example. Certainly enough to overtake the difference between them.
you don't state how 'having reason to believe that a shuffled deck looks different because of weaving' results in 'having information about the relative positions of cards in the deck'.
Surely this is true by definition? When I shuffle and present a deck (usually using at least 7 riffles, and a few overhand shuffles, so that the deck is sufficiently shuffled), I know nothing about the order of my deck, and have no reason to believe anything about the distribution.
If you have reason to believe your deck looks different, you have information about the relative position of the cards in it.
No, it isn't true by definition. Not unless you use a very strict interpretation of what having 'information about the position of cards' is.
Because the starting order of a deck influences the final result, any change in the initial order will naturally make the final result look different, given exactly identical shuffles.
While you may not have information on what that difference is, you can be certain that there is a difference.
The hole in the logic has to do with assuming all reasons and all differences necessitate knowledge about the position or order of cards in the deck. This is a false assumption.
Furthermore, this is at odds with your previous statement that weaving followed by sufficient randomization will not maintain that pattern at all, which I agree with. If you weave, and then shuffle enough that the order of the deck is randomized to the point that you have no knowledge about the distribution of cards, such as lands and nonlands, the weave had no effect, either positive or negative. But if you weave, then shuffle, and expect to still have reason to believe that your deck looks different as a result of the weave, then you have not shuffled to the point where the deck "does not maintain that pattern at all".
What if the difference is "The deck looks less like the initial order than if I hadn't weaved."?
Okay, I understand now that I wasn't being totally rigorous with my original bolded statement. Obviously if you could shuffle two decks with exactly the same shuffle, but one was mana-weaved, then you would have equal information about each deck's order. I'm not sure how this is relevant, though, because you never do exactly the same shuffle when randomizing a deck.
Let me try to be more rigorous in explaining my perspective. I would specifically like to refute your claim that "a weaved deck will have less impact on the final result than a fully stacked deck." I love examples, so here goes:
Setup:
I write a computer program that randomizes a virtual "deck" composed of 20 Mountains and 40 Lightning Bolts.
Scenario 1:
I stack the 20 Mountains on top of the deck and the program randomizes.
I instruct the program to find the largest land clump in the deck.
I repeat the first two steps 100 000 times, and find the average largest land clump.
Scenario 2:
All the same, except the input is a mana-weaved deck.
I believe that whether the deck was weaved will have zero impact on the final result.
I am absolutely willing to write this computer program if this would settle the debate. If it would not, I would find it very helpful to understanding your position if you could modify my proposal or write your own experiment that would express concrete, objectively observable results that would support your claim. I truly want to know if GAThraawn and I are wrong, and we have the tools to find out for sure.
So... if the deck being weaved, or being not weaved, will make zero difference on the final result, then mana weaving may consume more time, but it certainly isn't cheating. So, if it's something that people think will make them draw better, but in reality has literally no impact, it's nothing more than a superstition.
You can't call a superstition cheating, because you certainly can't stop me from wearing my lucky underwear to FNM.
But i personally feel if you start with a stacked deck, 20 lands 40 spells, when you get done shuffling, you're going to know more about the order of the cards in that deck than you are going to know about the deck you mana weave, and then shuffle.
In order to get the stacked deck to a sufficiently random order, you're going to have shuffle longer than a mana weaved deck, because the mana weaved deck is already "shuffled." (It's certainly in an order that is harder to recall information about than a deck with all 20 lands in a row, and then all spells in some stacked order.
A deck that starts from neither of those, such as what you would probably get after a game, is going to be random on one level, and have stacks of land and spells above that, which can lead to clumps of cards you can recall from previous matches, giving you prior knowledge about the deck. Unless you take the time to really shuffle it well, and be sure that it is random.
But, if you are going to shuffle that much, it isn't going to take any less time than doing a mana weave, and ensuring a nice, random assortment of cards, avoiding all clumps.
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Whats the big deal about black lotus you ask? Well you see, there is no big deal about it. It IS the big deal.
There may be clumps, but in general, not of 6-8 lands in a row. So yeah, you won't literally avoid all clumps, and they may still happen. But you certainly can't say after a mana weave that your sleeves were stuck together. But if you don't mana weave, you could do some expert whining on how sticky your sleeves are and why you drew a bad hand.
Mana weaving leads to less complaining. That's why i like it.
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Whats the big deal about black lotus you ask? Well you see, there is no big deal about it. It IS the big deal.
Let me try to be more rigorous in explaining my perspective. I would specifically like to refute your claim that "a weaved deck will have less impact on the final result than a fully stacked deck." I love examples, so here goes:
Setup:
I write a computer program that randomizes a virtual "deck" composed of 20 Mountains and 40 Lightning Bolts.
Scenario 1:
I stack the 20 Mountains on top of the deck and the program randomizes.
I instruct the program to find the largest land clump in the deck.
I repeat the first two steps 100 000 times, and find the average largest land clump.
Scenario 2:
All the same, except the input is a mana-weaved deck.
I believe that whether the deck was weaved will have zero impact on the final result.
I am absolutely willing to write this computer program if this would settle the debate. If it would not, I would find it very helpful to understanding your position if you could modify my proposal or write your own experiment that would express concrete, objectively observable results that would support your claim. I truly want to know if GAThraawn and I are wrong, and we have the tools to find out for sure.
I'm glad you're willing to put effort into this. Personally, I don't have the expertise or resources to create the necessary simulation myself. Just creating the randomization algorithm alone would take weeks of research for me to do.
I don't know your background with this sort of thing, but the most important thing you should ask yourself when creating a simulation is "Does this accurately describe reality?"
I can't answer that right now, because you haven't elaborated on what method you plan to use to randomize the virtual deck. Suffice to say, a simple RNG algorithm would not reflect what actually occurs when you shuffle a deck.
This can be seen by comparing a virtual deck randomized by an RNG algorithm to one that's been given a single iteration of a physical shuffle. You will see that with the virtual deck, any card can end up in any position but with the physical shuffle, there will be certain cards that cannot reach certain positions (eg. the top cards of a single mash shuffle cannot finish at the bottom of the deck).
For it to be accurate, it needs to mimic common shuffling methods. Good candidates are the mash shuffle and the riffle shuffle, which are specifically mentioned in the MTR.
Because physical shuffling is iterative, you need to be able to apply the method several times. Ideally, you should be able to record the data after each iteration (see below for why).
When recording data, too little is poison for good conclusions. You should record as much as reasonably possible! Especially if you're intending to thoroughly investigate the subject.
In this case, you should not just record the largest land clump, but the entire distribution of land and nonland clumps. That way you will have not just the largest value, but the mean, median, mode, lowest value, and other statistics that relate to the distribution of both halves of the deck.
Also, you should record the values for each step of the iterative process, so you can compare each iteration to both the original order of the deck, and to the same stage of the sister deck.
Parinoid has invented a term "represents", as used in the phrase "some configurations more closely resemble (or represent, if you'd prefer) a randomized deck than others." This term is not used in mathematics when discussing random numbers, and this poster has not provided a rigorous definition of it, so it would be dangerous to give it any weight until one is provided.
Furthermore, parinoid has claimed that it is unreasonable to truly randomize a deck in a timely manner, and accepts some lesser amount of shuffling as sufficiently random. However, as has been quoted in this thread, the rules require that you not have any information about the relative positions of any cards in the deck. If you have reason to believe that your shuffled deck looks different because of mana-weaving, you have information about the relative positions of cards in the deck.
So according to parinoid's logic, mana-weaving is always cheating, because, supposedly, true randomization is impossible. Unfortunately, according to this logic, it is also cheating to look at your deck, then shuffle and present it, which nearly every player does before nearly every game.
I personally believe that it IS reasonable to expect good shuffling from players that have good skill with their hands, but of course some players are slower shufflers than others. Players physically incapable of randomizing their deck should notify the Head Judge before a tournament starts and accommodations will be made for them if possible, however it is not the judges' responsibility to make such accommodations.
What knowledge or information are you claiming I lack?
It's used all the time in statistics, when considering if a sample accurately describes the population it comes from.
In this case, I'm stating that a deck with the lands interspersed evenly is more representative (ie. is a more typical example or specimen) of a deck that has been randomized through physical manipulation, than a deck where the lands are not interspersed, but all clumped in one section of the deck.
Note that I'm not claiming that it is the best example, just that it is a better one.
What information do you claim they would have?
Keep in mind that I've been constantly referring to weaving followed by sufficient randomization, which will not maintain the original pattern at all.
It kind of plays into my question, but the premise and conclusion in the third sentence don't follow logically, because you don't state how 'having reason to believe that a shuffled deck looks different because of weaving' results in 'having information about the relative positions of cards in the deck'.
I thought you should know, since you went to the trouble of bolding it and everything.
That's quite a leap. I fail to see how you've managed to show that a deck that is not truly random cannot meet the criteria of 'sufficiently random'.
And are you claiming that true randomness is obtainable through physical manipulation?
Was never in dispute, but good to know.
A mana weave is a way to set the deck beforehand to simply prevent clumping of cards, and ensure you can get a random shuffle. Then you know nothing will be clumped together once proper randomization begins. If you rifle a deck 7 times after you mana weave, you will not be able to predict what cards will come next. You can make a fairly accurate guess (As to say a few lands and a few not lands) but you should usually be able to say that if your deck has a proper land to not land ratio.
Even if the lands generally stay in a 2-1-2-1 weave ratio, they arent going to be the same lands in that order. So, if the lands aren't the same lands, would you say you still have knowledge of the deck? Here's an example. Say you run 4 sacred foundry (S), 4 blood crypt (B), 4 mutavault (M), and some other basic lands (L). If you mana weave it to look like...
S-2-S-2-S-2-S-2-B-2-B-2-B-2-B-2-M-2-M-2-M-2-M-2-L-2-L-2-L-2.......
and then you rifle shuffle, and make the deck end up looking like.
L-2-B-2-L-2-S-2-M-2-M-2-L-2-B-2-S-2-L-2-L-2-B-2.....
Do you know anything about the deck, besides the fact that every third card will be a land? I don't believe that you can make an accurate statement about it. Though that is in a perfect world, and the weave will not be retained. The weave will be broken, and then shuffled back together, and broken again, and shuffled together, and make it look like...
L-L-4-B-S-3-L-1-M-2-B-M-5-L....
So yes, if you do not shuffle the deck well enough, you are going to end up having knowledge. But the point is random is not real. It's pretty much impossible to get perfect randomization, especially because there are a set number of configurations that the cards can actually sit in. So, all wizards asks is that the deck becomes sufficiently random, and that you can not be sure what card is going to to come next. Even directly after a mana weave, you won't have knowledge of what card will come next, just the general ratio of land to spells. Once the deck is shuffled to change that, and the ratio isn't perfect, then the cards are sufficiently randomized, the deck is shuffled.
IMO, You're more likely to get a sufficiently randomized deck, if you start with everything spaced out somewhat. Because if you have a large group of lands and a large group of spells, and shuffling is certainly not perfect, it's going to be more likely for those like cards to stick together, and come to clumps of those cards. It's statistics. Which is why i always rifle my lands into my deck, and then rifle the deck a few more times before shotgunning for a bit and cutting the deck, then presenting.
These quotations capture what I find to be a problematic understanding of randomization. I am not claiming you can make a deck truly random through physical manipulation. Ask any physicist, and she will say that the only way to do that would be to set up some kind of quantum experiment like a photon reflectivity deal. Everything on a larger scale is deterministic. This is a futile conversation to go down.
In this thread, we define "sufficiently random" as "a state where no player can have any information regarding the order or position of cards in any portion of the deck" (TR 3.9). Here is my understanding of this passage stated as plainly as possible:
Scenario 1:
Scenario 2:
If these two percentages are different, I believe you have "information regarding the order or position of cards" in the deck. Specifically, you have statistical "information" about how well-distributed ("position") the lands ("cards") are.
Hopefully, shuffling one hundred times is not necessary, but it is the responsibility of each player to shuffle until they have obliterated all statistical knowledge they have about the contents of their deck. If I see someone mana weaving, I can be certain they are either wasting tournament time by doing so, or else they will go on to shuffle few enough times that they have statistical knowledge about the contents of their deck. That's insufficient randomization.
This boils down to a philisophical question. When you introduce chaos to a system (shuffling your deck), does the amount of order it started with affect the outcome? Like many have said, if mana weave has an outcome, you're not sufficiently randomizing your deck. This is theoretical. If you start shuffling a deck with 24 land on top and 36 spells on bottom, and present after 6 suffles, you will get hosed. In theory, it shouldn't make a difference. To achieve a true state of randomization, we'd have to take into account plenty of other factors. How new are the sleeves, where did the cards start out, do you shuffle top to bottom, top to middle, top to top followed by a pile shuffle.
There's just too many factors to achieve a true randomization. This is why the best bet is to shuffle your opponents deck ALWAYS, even if it is a simple pile shuffle. Sometimes when playing in a new store or a new player, I get dirty looks. I simply explain that shuffling your opponents deck keeps the game honest.
Anyone who is actually offended by shuffling their deck is either cheating, or is offended easily.
Surely this is true by definition? When I shuffle and present a deck (usually using at least 7 riffles, and a few overhand shuffles, so that the deck is sufficiently shuffled), I know nothing about the order of my deck, and have no reason to believe anything about the distribution.
If you have reason to believe your deck looks different, you have information about the relative position of the cards in it.
Furthermore, this is at odds with your previous statement that weaving followed by sufficient randomization will not maintain that pattern at all, which I agree with. If you weave, and then shuffle enough that the order of the deck is randomized to the point that you have no knowledge about the distribution of cards, such as lands and nonlands, the weave had no effect, either positive or negative. But if you weave, then shuffle, and expect to still have reason to believe that your deck looks different as a result of the weave, then you have not shuffled to the point where the deck "does not maintain that pattern at all".
Weaving and then thoroughly shuffling is a waste of time, but not a violation of tournament procedure, and I'm not going to actively stop anyone from doing it. But believing that it's acceptable to weave and then insufficiently shuffle, as defined by believing your deck still looks different than if you hadn't weaved, is a problem. I want to emphasize that, and the fact that mana weaving will at best raise the suspicions of other players and judges who may well be additionally suspicious of insufficient randomization.
If your question is "What would a judge do is this situation?", only one person's answer is relevant, and that is the Head Judge at your event. I can quote the rules, but I don't know your HJ.
This exactly. No matter how expert a person is, they can still make mistakes and should not be above reproach.
You seem to have misunderstood my point.
What I've been trying to say is that the benefit from weaving is that a weaved deck will have less impact on the final result than a fully stacked deck.
That implies that it is harder for one to retain information about the relative position of cards if they weaved first, when compared to if they stacked it in a 20-40 fashion.
I don't understand how one would obtain percentages like what you've used, but in your examples the margin of error in the first example would be much larger than the margin of error in the second example. Certainly enough to overtake the difference between them.
No, it isn't true by definition. Not unless you use a very strict interpretation of what having 'information about the position of cards' is.
Because the starting order of a deck influences the final result, any change in the initial order will naturally make the final result look different, given exactly identical shuffles.
While you may not have information on what that difference is, you can be certain that there is a difference.
The hole in the logic has to do with assuming all reasons and all differences necessitate knowledge about the position or order of cards in the deck. This is a false assumption.
What if the difference is "The deck looks less like the initial order than if I hadn't weaved."?
Let me try to be more rigorous in explaining my perspective. I would specifically like to refute your claim that "a weaved deck will have less impact on the final result than a fully stacked deck." I love examples, so here goes:
Setup:
I write a computer program that randomizes a virtual "deck" composed of 20 Mountains and 40 Lightning Bolts.
Scenario 1:
Scenario 2:
All the same, except the input is a mana-weaved deck.
I believe that whether the deck was weaved will have zero impact on the final result.
I am absolutely willing to write this computer program if this would settle the debate. If it would not, I would find it very helpful to understanding your position if you could modify my proposal or write your own experiment that would express concrete, objectively observable results that would support your claim. I truly want to know if GAThraawn and I are wrong, and we have the tools to find out for sure.
You can't call a superstition cheating, because you certainly can't stop me from wearing my lucky underwear to FNM.
But i personally feel if you start with a stacked deck, 20 lands 40 spells, when you get done shuffling, you're going to know more about the order of the cards in that deck than you are going to know about the deck you mana weave, and then shuffle.
In order to get the stacked deck to a sufficiently random order, you're going to have shuffle longer than a mana weaved deck, because the mana weaved deck is already "shuffled." (It's certainly in an order that is harder to recall information about than a deck with all 20 lands in a row, and then all spells in some stacked order.
A deck that starts from neither of those, such as what you would probably get after a game, is going to be random on one level, and have stacks of land and spells above that, which can lead to clumps of cards you can recall from previous matches, giving you prior knowledge about the deck. Unless you take the time to really shuffle it well, and be sure that it is random.
But, if you are going to shuffle that much, it isn't going to take any less time than doing a mana weave, and ensuring a nice, random assortment of cards, avoiding all clumps.
If your deck is sufficiently random, there might be clumps! If you've managed to avoid all clumps, and you know this, it sounds like you have cheated!
Mana weaving leads to less complaining. That's why i like it.
I'm glad you're willing to put effort into this. Personally, I don't have the expertise or resources to create the necessary simulation myself. Just creating the randomization algorithm alone would take weeks of research for me to do.
I don't know your background with this sort of thing, but the most important thing you should ask yourself when creating a simulation is "Does this accurately describe reality?"
I can't answer that right now, because you haven't elaborated on what method you plan to use to randomize the virtual deck. Suffice to say, a simple RNG algorithm would not reflect what actually occurs when you shuffle a deck.
This can be seen by comparing a virtual deck randomized by an RNG algorithm to one that's been given a single iteration of a physical shuffle. You will see that with the virtual deck, any card can end up in any position but with the physical shuffle, there will be certain cards that cannot reach certain positions (eg. the top cards of a single mash shuffle cannot finish at the bottom of the deck).
For it to be accurate, it needs to mimic common shuffling methods. Good candidates are the mash shuffle and the riffle shuffle, which are specifically mentioned in the MTR.
Because physical shuffling is iterative, you need to be able to apply the method several times. Ideally, you should be able to record the data after each iteration (see below for why).
When recording data, too little is poison for good conclusions. You should record as much as reasonably possible! Especially if you're intending to thoroughly investigate the subject.
In this case, you should not just record the largest land clump, but the entire distribution of land and nonland clumps. That way you will have not just the largest value, but the mean, median, mode, lowest value, and other statistics that relate to the distribution of both halves of the deck.
Also, you should record the values for each step of the iterative process, so you can compare each iteration to both the original order of the deck, and to the same stage of the sister deck.