From the exerpt online (an article in Men's Health - May/June 2005) it appears there are some sound principles in the program, like the 6 meals/day strategy. But I'm not impressed with their macronutrient ratios, and the exerpt doesn't say how they prescribe total caloric intake.
They also claim 5-7 pounds of lean mass gain in "as little as 4 weeks", a gain of nearly 2 pounds of lean mass per week. If this system truly did that, it would have been on the front page of the Wall Street Journal 2 years ago.
The rudimentary periodization it describes is good stuff, too. But it also puts out a "one size fits all" workout plan, which no major certifying body for trainers would endorse.
I don't see any real danger in trying it out, and I'm sure the book is cheaper than going to a good trainer for a workout & nutrition plan. If this is your best option, I'd say go for it - for now. BUT - approach the heavy lifts with a great deal of respect, and use a training partner to spot you for these exercises:
Barbell Front Squat
Incline Bench Press
Hang Clean and Press
Be particularly aware of discomfort in your knees, lower back, and shoulders - particularly a pinching feeling in the shoulders - and stop and consult a professional if you have a problem. Do not try to "work through the pain".
Good luck. Let us know how it goes.