Eternal Witness and Cabal Therapy worked pretty well in a BBE based Jund Rock list I tested a long time ago. It's a couple more good cards to Cascade into, and they fit with the attrition/card advantage theme. I played Dark Confidant over Sakura-Tribe Elder. And didn't play Wasteland, because it almost always hurt more than it helped in a mana hungry midrange deck w/o Aether Vial. Goblins and Merfolk can get away with it while still progressing their board state with Vial or Lackey; this sort of build is really top heavy and I think it hurts more from the tempo loss of an early land drop than most decks.
The problem I found with this build/strategy is that while it could grind out amazing verus "fair" decks: agro and control, it got steamrolled by combo and didn't have much game against the "ooops I win" sort of plays, like Natural Order into Progenitus, or Loyal Retainers into Iona, etc. I was working on it when Zoo and Merfolk were on their initial rise just after Alara Block, but abandoned it when CBT moved to running Natural Order and Reanimator came onto the scene with Iona. I don't really have much else to offer, I just don't think Bloodbraid Elf stacks up against Natural Order and Show and Tell and what not, if your meta is mostly straight forward, no tricks, agro and control, then this sort of list can catch people off guard, but in a diverse meta I think it's a clunky deck.

