"why didn't anyone wearing a hakama ever explain it so clearly as these guys wearing sweats and tee-shirts?"
it is in there, but I think we as a community have done a very poor job of codifying and communicating it.
I won't answer for John, whom I know. But I think it is because early on we accepted nomenclature for our physical comprehension as a substitute for intellectual comprehension. Ki, Aiki, Kokyu, Musubi Takemusu, all are valid objective concepts, but initially, it is hard to get over the change in manner of moving so that more commonplace concepts like "push" "pull" "stand" and "move" are hard to segregate from the manner of prior experience without a different category of naming. I mean this of any serious fighting art.
One of the first things that I realized when I began to break the nomenclature down (not to destroy it but to reshape in my native terms) and teach for new guys is the change that must occur under threat if one is to fight well. It is quite simply demonstrated -- fight or flight -- for flight the body tenses, the Cg rises and one is prepared to dart away. To FIGHT on the other hand, the body must relax the undercarriage compressing it slightly, and all the body's frame has to pull relaxedly into itself, gathering into
the threat within itself, as it were (first action of irimi?), and not away from it.
That's why I am so (annoyingly to many, no doubt) seriously exploring the physics of relaxed, linked structures and the biomechanics that go with it. It is helping to put some Western objective content into the nomenclature. The purpose is not to replace the traditional nomenclature - it captures concepts in a different ordering than we do, and is useful in its own right for that reason. The purpose is to relate it more clearly to our ordering of those essential principles.
The guys in sweats and tee-shirts are not burdened by the nomenclature -- but then, they do not take the benefit of it either. It is rich in its own right, and the baby should be held onto -- whatever one does with the bathwater.