Freeing yourself from the classical mess.
A lot of traditional martial arts makes you stand in punishing stances for long durations of time. Or punching in the air for months. Bruce felt this was a waste of time. A means to test the students dedication and worthiness to learn the instructors art. There was many students and why should an instructor waste time on someone not dedicated or serious about training. Tests of students outside of schools in ancient china where potential students would bow and bang their head on stone streets causing their forehead to become bloody and bruised. While spending days/weeks outside a school in hopes to gain entrance. Horse stances, grueling workouts for no reason. These were some and are still the part of a lot of traditional arts. Commercialism has forced business to change of course. But Bruce felt this way about traditional arts and forms and Katas in both Chinese, Japanese and other cultural arts. Forms is not alive movement. He felt it was dead.
Here you can see after the fight with Wong Jak Man Bruce started to look at a different track for his personal growth. He kept some aspects of Wing Chun but also removed himself as limiting it to the confines of what he trained. He felt there was a lot that Wing Chun offered but it also limited himself. At this time he also delved into a lot of physical fitness training within his martial arts.
I can remember as a kid doing forms and at some point mindlessly going through the motions as if it was a dance. Not emotion. No thought. Just another completion of that particular form. It was when we broke it down and trained its application did it bear weight to me.
My personal thought. Well some of the grueling stuff does benefit you a little. But i think there are much better ways to train. Alive drills is better.
Or as Bruce use to say. Fighting is like swimming. You have to get in the water.