What will happen, what will the physics denier say, when someone does bother to do a broad and deep study of an IP practitioner's movement, and what the practitioner is doing is explained by biomechanics? There seems to be a strong need in some folk to keep very special what they do vs what other people do.
No one's saying that it can't potentially be explained by biomechanics - they have said that existing attempts with current models don't work very well.
Also, IME, getting a very fine grained understanding of exactly what tissues are doing what only gets you so far. Past a certain point it's interesting, but it doesn't really help you to do - which is what most folks are interested in, I'd say.