Playing a puzzle game in front of a developer is a nerve-racking experience, let me tell you. At some point, your brain will betray you. You'll get stuck. And since the game is still being made, the developer won't want to provide any hints. None. You're on your own looking like a complete fool.
Playing a puzzle game in front of a developer -- in this case, Braid and The Witness designer Jonathan Blow -- and an audience, both in-person and online is ... I can't even fathom.
That out of the way, The Witnesslooks fantastic in this gameplay demonstration out of PlayStation Experience. Keep forgetting this is a 700-puzzle, 30- to 40-hour game.