If you are referring to the exercises posted on here then yes it does work. Many people have made gains (DLD over 4 inches in length), i advice that you check out the newbie section.
Yes I know about the workout part but the biochemicals that is talked about restarting the growth but replacing the biochemicals the body stopped producing at the end of puberty. That is what im talking about its a neat idea. If it works that is
The Penis Bible is more of a cartoon comic book. Do not believe the idea of restarting puberty. Messing with your body chemistry is a tragedy waiting to happen. It wouldn't just affect your penis anyway.
That book has a lot of irresponsible "information" in it. Remember its primary purpose is to make money.