As an introduction to formal systems[1], it's great. For a musician, it totally falls apart in the "Bach" section. The idea that the circle of fifths[2] (or any progression that ends where it started) is a "strange loop" is just silly. There's nothing strange about it. Traverse a sequence of (usually 12) integers that slice up the octave by using any integer for step size and bang! You eventually land back at the beginning of the sequence.