I was the player that got dismantled on camera by Owen Turtenwald in round 4. I made many misplays on both a strategic and tactical level, especially in game 3, where I tried to make a cool but incorrect play and ended up on the wrong side of a 3-for-2 as a result. I went 5-3 in day 1, missing day 2. I lost to Owen on Hollow One, Tron, and Mardu Pyromancer. I had one bye and beat Hollow One, Storm, Burn, and Sun and Moon. I was not at the top of my game, and I think with tighter play, I could have turned two of my three losses around (not the Tron loss, just got blasted).
I played only 2 BBE and cut all 3 Fulminators for 3 Leyline of the Void, thinking that I cannot beat both Tron and Hollow One with Jund, and so I should pick which one I actually want to beat. This ended up mostly working out, as I only lost to one big mana deck (Tron) on Day 1. Leyline was nice. I know I lost two games to Hollow One on camera with it, but overall it felt like a strong and useful sideboard card. I also played 2 Cage and 1 Anger as GY hate, and in the future, I think those Cages should be Nihil Spellbombs to make topdeck Leylines less bad. I don't think this is too much graveyard hate. Hollow One is a really hard matchup that requires serious concessions to turn around. With the sideboard configured as such, I think it's 50/50 or maybe slightly better.
Overall, I do not think Jund is well-positioned at the moment. I have never felt my sideboard stretched so thin in all my years of playing this deck. Bloodbraid Elf does not solve any of our current metagame problems whatsoever. Right now it is just a fun card to play, nothing more. I personally find it enjoyable to try to interact no matter how futile it seems, but make no mistake: this is not a tier 1 deck right now.
EDIT: for reference, the decklist I played in the GP:
I think the maindeck is great, sideboard going forward should be -1 Duress, -2 Cage, +2 Nihil Spellbomb, +1 Grim Lavamancer