I do agree with you on the fact that Bruce Lee's training program changed and evolved that was clearly noted in his book mentioned above.
What I have gathered from my Bruce Lee research, is that his philosophy was -- "use what works throwout what doesn't work"
So in keeping with that philosophy; it is obvious that Bruce Lee's training program would continue to evolve. The knowledge that he put into his training program was based on 1970s research of exercise physiology. Today, there has been new research and medical studies that shown more effective ways of training. That doesn't make what Bruce Lee did a incorrect it... just means that now there are better ways of exerciseing
Although Bruce Lee was ahead of his time in the fact that he utilized his own -- high-intensity interval training -- in fact most of his workouts utilized circuit training. He felt is was most effective way to achieve the strength goals that he wanted. (In my opinion)
Unlike most individuals today he wasn't all about what system or one -- "Ism."
Unfortunately today many individuals adopt one system of training and believe that that is the end-all be-all. It was the same way when Brazilian jujitsu was introduced into United States. No one believed that a grappling art would be superior to a kicking and punching art.
Yet, what has mixed martial arts shown us?
Just my two cents. No insults intended
Thread: Bruce lee