At a point your power is disruptive and your hands do everything you need without much overt body movement. If you were trying to make a waza "shape" you would have to withdraw power to fit the shape, otherwise you would just control them and ruin the "shape" of a technique.
The same thing applies to weapons kata. When they touch your sword-their hitting transparent power-the ground is present in the weapon and a movement will launch them or cast their weapon without much effort. In and of itself it is disruptive to kata.
Thanks Dan, that's what I thought you were getting at. I was going to say that when you get some measure of that soft power, you will probably already be seeing an end to techniques as they are typically performed. All of the things that the techniques are supposed to guide you to feel and achieve happen long before the end of the technique. When you're doing all the things in you that you should be doing, things happen that can't always be stuffed back into whatever technique your instructor has you doing and trying to do so becomes counter-productive to what made that all happen in the first place.
I have my thoughts of how that may or may not change when you have those skills on both sides. I think it could be a much more active thing and kaeshi, something I think most aikidoka consider "advanced", becomes the next logical step and the next thing that "just happens" as the result of what's going on in you. Unfortunately at this point it is just a thought though.