Now we're getting somewhere. It has been the lack of the relative idea and caveats from Dan's perspective that have troubled me, far less so in your usage, after much discussion. That image is almost exactly how I get my occasionally sloppy uke to close his line in commencing katate menuchi -- by offering and holding in wait a prospective kick for him as his blinking, red-light "Honk honk," "I'm going to hit you" signal.
Seems not so different, actually. I'll have to try it in static isolation. As I have said, my perception is that we come at it from the other direction. Closer to static, I've done and occasionally demonstrate a variation where you engage katatedori while high up on the balls of both feet, let him try to get his push going -- and then drop him into kuzushi. To me it exemplifies the use of ten no kokyu. It seems like the more on tippy-toe you go all the more enticing it is for uke to try that much harder with the push -- and really sucker himself.
Would that be the kind of thing you
mean in "not moving?"
It's a simple statics analysis, Erick. It's all right in front of you. "Not moving", in the case of this simple example, means that an equilibrium of forces has been achieved. A simple vector analysis should expose the basic "secret" to the most casual observer. Being able to move with this skill manifest, and manifest in all directions simultaneously, is it. Of course, this example is like plucking and releasing a string in order to make a tone.... it is not the full virtuoso classical-guitar playing, by any means.
However, this is the obvious fruit that has been dangling for a few years right in front of you, while you seemed intent on abstruse solutions. Just do the static-analysis and look at the solution vector that nage needs to generate in order to achieve "not moving". That's the key (pun intended).