Well, the guy who wrote the Shadow Divers didn't have much of a storied history in regards to literature. I think the most he had ever written were some books about the Three Stooges. Richie Kohler and John Chatterton actually hired him. When researching for the writing of Shadow Divers, rumor has it that he didn't conduct many interviews with other divers, and most of his material came directly from John and Richie themselves. Some say they wanted it that way so they could embellish more, and affect the writing in a way which would cause it to appear they were more "hero characters" than bystanders as they were in some of the situations described in the book. It worked. Not only did the success of the book help them nail down their TV show "Deep Sea Detectives", it garnered them both enough fame to get Hollywood to contemplate making a movie over the past couple of years. It also spawned a NOVA documentary show about it, which ironically enough, certain parts (the parts box recovery for example), were filmed a few miles off the coast, and not at the site as implied. Anyway, Ridley Scott was originally slated to direct the movie, but that fell through. Who knows where it's at now. Most of us kinda got burned out on the whole thing and stopped keeping track of it.
Not to take away from the book though. It was actually quite good. I enjoyed the book, even though I knew more about the story than the average reader. And his historical accuracy is relatively good (with some minor mistakes) as is his explanation of the dangers of deep wreck/technical diving. And let's face it, in their defense, Richie Kohler and John Chatterton are quite skilled and highly respected, even after the Shadow Divers "debacle". They both have done some amazing stuff along with some other pioneers, and my mask is off to them, and they actually spearheaded a great awareness of U-boats in American Waters, and the history behind them.
I just wish more credit was given to the several other divers who were just as involved in the story than they were, some of whom didn't make it back alive.
As stated, check out
http://www.ggentile.com/ and take a look at his non-fiction book list for Shadow Divers Exposed. I own almost all of his works, and have actually talked to him on a couple of occasions when I had some artifact preservation questions. Good stuff, and quite the brutally honest fellow. By the way, he was actually on the boat when several of the situations in Shadow Divers took place, being a member of the elite technical diving pioneering cadre.