It's not as popular as it once was. It once was the "in" thing back in the day.
Everybody was into "bill phillips and his body for life."
If you follow some things he says, yeah it'll work pretty well for you. It worked for many people. It's not really anything earth shattering, it's basically different routines and different eating habits that many other people have talked about and written about years ago.
THe problem with his system was he started coming out with new and improved ways and more books for MORE MONEY and everybody saw him as what he was, just another greedy money grubbing con artist.