I have the bodyweight-version of that book called "Never Gymless". It is the best work-out book I've ever bought. I've religiously followed its principles and my conditioning is phenominal as a result. We once had a hill-sprints race at my gym. Everyone participated. I came in first by a wide margin. My explosive strength has benifited amazingly. My coach is amazed by my physical talents. I'm not being puffed up, I give the glory to Ross Enamait. If you want to be a stronger, more conditioned boxer by all means by one of his books. Worth their weight in gold.

ps. yes he is a boxing trainer and has been for a decade. He has been boxing himself since 4 years old, but his career as a boxer came to an end with a bad brake in his hands. He reverted to coaching boxers and has had much success. In fact, he was the conditioning coach for Chad Dawson among quite a few other big names.