Originally posted by anerlich
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“Bruce applied WC concepts to everything he did, WC or not, including large circular techniques that are not nearly efficient enough for Wing Chun to call her own.”
I think that’s highly debatable. Bruce was moving away from rather than deeper into WC toward the end of his life. WC people seem to coopt Bruce as a poster boy when it suits them, trash him when it doesn’t.
[/B]
Not really.
This is very clear upon review of what JKD is and how it came about as well as Bruce’s writings on the subject.
Bruce expressed thoughts on refining and tightening up Boxing movements, he felt they ‘lacked directness’ and were expressed in an exagerated fashion with too much wasted movement. He attempted to streamline them.
He created the JKD Hook Kick by applying WC concepts to the Round Kick.
He applied these concepts using tools from Wing Chun and Fencing to create his Lead Straight.
He applied the same concepts to the traditional side kick.
Those who sparred with him or observed such training have commented many times that Bruce would play around a lot with different things, but when it got serious, he would stop hit, enter and trap, I can relate.. 
Bruce was not allowed to teach Wing Chun, he also hadn’t finished the system, so he adapted all the theory he had to what was available to him, and he created JKD, The Way of the Intercepting Fist, essentially encapsulating Wing Chun theory in the name JKD itself.
JKD is generally thought of as a Wing Chun derivative. Dan Inosanto has commented many times that the core art of Bruce’s JKD was Wing Chun. Dan goes on to say that he applied more of a FMA core to what is now his JKD.
When Bruce came to the US he was a Wing Chun guy bottom line, that’s what he had trained, bringing all the strengths and weaknesses that comes with it. He continued to grow and develop but clearly the driving concepts and theory applied to his study and creative process was very much Wing Chun.
After all, that’s where Bruce came from and, after all, these are some of the most thoughtful and powerful combat concepts ever devised, spawned from thousands of years of combative, mathematical and philosophical, et al study in China – this is what drives this system, the concepts are unbeatable, but it’s up to those training to put them to good use and that’s what Bruce did.
Anyone who thinks basic Wing Chun concepts can’t be applied to X, where X is come kind of physical dynamic with a tangible objective doesn’t get the concepts IMO.
Try and reinvent the wheel? No way! Try and replace a wooden horse and buggy wheel with a steel belted radial – Yes, any day!