"Allows" is different than "does". The problem with theory is that it's a tricky platform that often disappears the moment you try to put it into action. Which is why many games sound so great on paper, but end up selling so poorly.
I actually remember a game about 8 or 9 years ago that got the kind of over-hyping that LBP does, for a lot of the same reasons. It was supposed to be the game that would launch the DreamCast into the stratosphere because it was so ahead of its time and let the player decide how the game went more than the game itself did. That game, Shenmue, ended up being a permanent money sink and did not even come close to making the DreamCast blast off into sales history.
Sky Render - Sanity is for the weak.








