I researched his approach to working out and eating quite a bit last year - in fact, if you regularly read some of the fitness magazines that are more serious, some of the techniques he talks about (weights until failure, short high bursts of interval training, no more than 20 minutes) are being touted now for better and more efficient fitness results. There is a book I'm reviewing called the no cardio diet - he stresses weights to failure and a severely restricted diet (1300 calories daily for women and 1500 for men with uptapering over 8 weeks, but always eating a fairly calorie restricted diet) - however, as this author, DeVaney and some others, the interval training and training to failure is the key. DeVaney goes into his explanations through evolution, whereas the others use the results of their clients.
However, he is awesome for his age - there's a guy at the local military gym here that is cut like him and looks great - one of those older very distinguished looking 'hot' gentlemen. Nice eye candy when I'm working out ;-)