I have to add, a lot of Sir bernhard's ideas agree/ complement with Dr. Chang. As for beginners and confusing parts... reading bernhard's posts have been the missing link for me. More in depth (imo) and, thank goodness, easier to understand!
I read Dr Chang's book and found it interesting, but also had a few very specific criticisms....
Final criticism for now: self praise and testimonials. I'm pretty sure the "review" of the book was written by Dr Chang, and that's just something you're not supposed to do. You're supposed to pay someone from a minor newspaper or magazine to write an effusive blurb.
On a related note, linear learning, math, etc: There is a lot of discussion about how quickly one can learn a piece, how many minutes it should take to do a certain task, etc, and really, this is an oversimplification at best. Some things come more quickly than expected, others take longer, and applying a rigid equation to learning speed is in general counterproductive. Sometimes we hit not just a "speed wall," but a big fat learning wall. Sometimes we make rapid progress overnight, and other times we plateau.
First off, writing style and mechanics: This book read like a series of compiled message board posts, as opposed to a coherent book. It is repetitive and/or rambling in all the wrong places but fails to flesh out some of the important details in places and really feels like it is in drastic need of an editor, or at least someone to read it with the red pen in hand. I admire that it is self-published in many respects, but it could certainly be improved by a careful, thoughtful overhaul. If it were up to me, the book would begin by introducing a standard practice routine for a day, then it would break each aspect of that down and analyze each facet, then finally conclude by reexamining that day's practice, in light of what was discussed above. I think that with good editing, the book could be about 1/3 the length.
Next, lack of diagrams: it would really help to have the passages of music referenced in the book printed in line with the text, so that the reader can understand what is being discussed. The whole piece doesn't need to be there, just the specific bars.