So, in practical terms, is isolating out one structural component of the muscle, while ignoring the other aspects of the contractile machinery, useful as an overarching strategy for the practice of martial arts? Would it optimize the performance of the whole system?
Without the fascia component, you can't really do the "whole-body" thing. Without the whole-body approach, the jin advantages don't appear. It's a complex subject that goes much deeper than this, but understanding the "whole-body" part is a fair contribution so that people can begin to see the relationship between the qi/ki/fascia and the jin/kokyu-ryoku aspects.