I just realized that you wrote kokyu ho not kokyu nage... Kokyu ho dosa in Doshinkan has 10 different very specific variations, with very specific outer physical details.
NP Ron... I'm not familiar with how the Doshinkan does it 10 different ways, but I would suspect it comes from DR (maybe?), and it'd be in the 10 basic directions? I assume that's done in seiza? In any case, wouldn't it be variations on the same thing? I.E. at a fundamental level, expanding the groundpath in *any* direction, and using the breath to hook up the "suit"?
So, technically speaking, all those variations of kokyu-nage would essentially be variations of the same thing, would it not?
OK, maybe make it a little simpler... let's take a really basic exercise like funekogi undo where you're expanding/contracting in one plane only... same idea? How about doing funekogi without moving at all? I.E. simply stand as you would as if in preparation to do funekogi, BUT without the forward/backward rowing motion? What would you be training then? How would you be training? What is it you're working on?
Then, if you want to talk about "testing", have someone hold your wrists and push gently, straight in with a constant force, whilst in that position. Can you bounce/push/throw them off - without moving? How much arm/shoulder are you engaging? Where is your power coming from? And how is that the same/different to basic kokyu-ho where you simply throw the uke up and back, or to the side?