Apocalypse World. Hands down. Vincent has been refining the notion of teaching the players of his games how to actually play the game -- as opposed to just presenting a bunch of rules and then hoping the players get it. And thus far, Apocalypse World is his masterpiece. It is clear that it is teaching you one way to run games and then provides a ton of very specific things to do in order to run the game the way he wants you to.

Really, on reading this and thinking about it, it's kind of amazing that this is a new technology. But it is. And it's remarkable how different it is from most games in this regard.