I read it years ago, and while I don't follow it strictly any more, I'd say the general concept still makes sense to me.
IF you have a copy, read it and try it. I have a few friends who had good results as well.
In a nutshell (and keep in mind this was written a long time ago) it is a cyclical low carb diet in which periodic carb loading windows are used to create insulin spikes that drive a hormonal response.
It's easy to read my one sentence description and think "Well duh, you got Carb Back-Loading and all that" except I believe this book goes back to the 90s. Certainly no later than early 2000, so in that regard it was way ahead of its time.
In addition, Faigin is a lawyer, not a doctor. It was just an area of passion that he heavily researched and from that standpoint the book is one of my favorites. This guy just loved the topic, researched the hell out of it, and wrote a book with more references than any book I've read since. If you can find a copy it's worth a read.