I liked it...but I'm biased to a book that is in the context of Goju.
It tended to try and be a bit too systematic with deciphering applications, but its not suppossed to be a book of step-by-step learning...it's more a book of learning how to learn by thinking in terms of principles. Some of the interpretations I disagreed with...but again, it wasn't a book of specific interpretations - more how to arrainge and prioritize the possibilities....whatever possibilities you happen to come up with.
Victor made a good point about it depending on where you are in your training. that makes a big difference with just about any book. It's the reason we can read 'Book of Five Rings' every 10 years during our lives and understand a new meaning each time.
so from where I'm standing today...this was a good book and worth the read.