I agree Rupert. Using the "whole" body as a connected series of springs, fulcrums and levers is far more efficient kinesthetically. Can this be defined as "kokyu" then?
In answer to Mike's earlier question.
Throw them how? Kaitenage? It's easiest to learn to bring power to your hands/arms straight ahead because there's less strain on the shoulders and elbows. Too much strain on the shoulders and elbows makes the normal strength kick in and you want to stay relaxed and avoid that.
I think the analysis straight ahead with a push is a fairly clearcut way to try and define what is kokyu power.. and then apply the basics to all directions. Although someone may have a better way they can suggest.
Simple! No technique! Just use your kokyu power from center to hands and spiral the power left or right thru uke's center and manipulate their center thusly. My teacher Takeda Yoshinobu and some of my sempai can do, have done this to me. I have felt it. I'm close to doing it occasionally, but not as consistently as I would like.