I'd like to think that the absurd conclusion of Active Design would be mazes everywhere to increase walking distances, and of stairs that go too far up, and back down again.

That said, you're especially right about how staircases can be beautiful things. Case in point, the glass staircase in Siebel. It's absolutely gorgeous and ties the building together like a cinched belt ties an outfit together. Unfortunately, walking up more than one flight on it takes twice as long as any of the other staircases in the building, so it is perhaps less used than it could be.

I think it's also interesting to think how Active Design ought to become more important as population density increases, while at the same time perhaps making it more difficult to implement (how do you do active design in the sort of tall building where one must use elevators?).