Do you realize that Kevin Cron, the guy who was playing the Stax deck at GenCon, is one of the pioneers of the deck? He's been playing it for more than a year, he Top8ed at GenCon last year with it, and he surely knows what he is doing. Balance is REALLY good, It's definitly a skill-tester but It win games on its own. And Hurkyll's Recall, while being quite random, has multiple advantages and an excellent synergy with Trinisphere and Crucible of Worlds.

Not running Balance in Stax is wrong, imo.  If Balance were unrestricted, this would be the deck that would run 4.  Hurkyl's is to bounce your opponents moxen so that they can't work around your Trniisphere.  And Demonic Finds STRIP MINE and Balance.  If you didn't notice, Strip Mine is RIDICULOUSLY powerful in this deck.  I still think that 4 cards >> 2 that Thirst gives you.