I haven't read the whole South beach book yet (I bought it for my wife, she read it, and I've just skimmed it so far), but to me it just looks like a poorly edited copy of Atkins. It was immediately obvious to me that Dr. Agatston did not actually write the book himself, but rather it is actually a collection of articles written by different authors with slightly different ideas, and that the editor(s) were pretty careless about synchronizing the concepts.