Which is what I said, earlier, regarding Yi-Chi-Li (but I seem to be under the Curse of Apollo... ). Yi (Shin) drives Chi (Ki)... which drives the body and the outward expression of physical power and waza. Kokyu assists in the creation of spherical force ("peng") by providing a little boost to the change in atmospheric pressure in body cavities, until the individual is able to use other means to create the structural force by other means (manipulating internal tissues instead of depending on kokyu).