I'm confused... The introduction allows twists of 60 degrees, but the explanation seems to switch to assuming 180 degree twists.

What am I missing?

edit: ah, I missed an "at least" at the beginning. He shows god's number is *at least* 27 (I misread this as meaning exactly 27). And he does this by showing god's number for the uncolored flat cube is 27. The uncolored flat cube happens to be equivalent to the colored cube with 180 degree twists.

Though... given that, the colors like a bit of an unnecessary red herring. Just a literary bridge I suppose? From his amusing introduction about a magic schoolbus running over rubik's cubes?