I've come to the conclusion that any deck besides single-minded aggro may want to play this card and any deck that leans at all controllish probably will want to. Five life isn't quite worth a card, but shuffling a bunch of business back into your library is very good. Provided you don't have land in your graveyard, you're reducing the odds of drawing land, which is basically drawing extra cards.
Example: On turn 8, you've got 25 cards left in your library. You've got 6 of 17 land in play and don't need to draw any more lands. You've got 5 cards in your GY.
Pre-elixir your library is 11/25 land = 44% to draw a land
Post-elixir your library is 11/31 land = 35.5% to draw a land
There are caveats about tempo and all that, but the longer the game goes, the more it favors the person playing elixir. Also there's the resistance to mill.
Probably not good enough. I think in a controlling deck, there are actually more incentives to having stuff in your graveyard than shuffling it back in (archeomaner, rise from the grave, spelltwine).
I always try to snag one every draft just in case I run into Mind Sculpt.dec. It's also nice to side in for grindy attrition matchups. They usually go pretty late so there usually isn't much opportunity cost to it.
I don't mind having one for the sideboard, but I don't prioritize the thing. I'd typically take another dude or a more common sideboard a la Naturalize, but I really don't mind seeing one say with 6 cards left in the pack and nothing else.
I haven't played one in the main once yet, though.
Example: On turn 8, you've got 25 cards left in your library. You've got 6 of 17 land in play and don't need to draw any more lands. You've got 5 cards in your GY.
Pre-elixir your library is 11/25 land = 44% to draw a land
Post-elixir your library is 11/31 land = 35.5% to draw a land
There are caveats about tempo and all that, but the longer the game goes, the more it favors the person playing elixir. Also there's the resistance to mill.
*DCI Rules Advisor*
I haven't played one in the main once yet, though.