I finally got to try this exercise and it's eerie how easily it works.
I tried it with a friend who is not my student and who has often surprised me with what he can do. In agete, for instance, he can often raise his hands very effortlessly before I can resist, but when I try it, he feels me moving and can lock down and seal me off.
This time, though, I did as you described and he just floated back. Time after time, he couldn't resist. Very interesting.
Good, it's not just me imagining things then!
One of the many things that I have discovered in my aikido journey is this: Aikido is hard to master, because it is so easy to do!
The effortlessness that can be achieved, usually isn't, because of the effort being employed in trying.
Then I did agete the way Dan showed me. I could never get it before: it involves letting his power go down the front of your body, into your feet, down into the ground and back up under the opponent's feet, going up into his body. At the same time, your own power goes up your back, out the top of your head and over the opponent to come down behind him. And then you just raise your hands straight up and he can't resist.
In the past, I have been unable to sustain both of these directions of intent at the same time and I've never been able to make this agete work on this particular training partner.
This time, I used my ki to direct where the force would go. If you tell me, put your mind here and also there, I couldn't do it. I could establish the power down my front and up into him, but when I tried to bring my my own power up my back, I lost the power in front. Because I was trying to put my mind in both places at once.
This time, using ki, it was like saying put one hand here and the other hand over there. The mind doesn't do it: it directs the ki to do it. I can reach into both places at once with my ki and sustain it in both places at once because, again, the ki is a part of me like my hand(s). I can put my hands in two places at once, but my mind is pretty singular. I've only been able to put it in one place at a time. But my ki is just like my hands: I can put it where I want it and keep it there while also doing something else. The mind just directs and observes.
So I was able to set up both types of intent and then I just lifted my hands straight up and my friend was unable to stop me. He could feel it and could tighten down on it, but when he did that, his feet would come off the ground and he would "float" back several inches. And I felt like I wasn't making any effort at all. It was really a blast and very satisfying.
I may have to experiment with some more of this at practice this evening. I do a similar hand raising exercise, but with different imagary, similar results though.
Except for one thing: he could let go (or my hands just broke through his grip). I remember when Rob John did agete with me, his arms were spaghetti but I couldn't feel him moving, I couldn't stop him and I couldn't let go. If he had brought his hands back down, I still wouldn't have been able to let go and he would have given me whiplash.
I like the spaghetti description of the arms, rope or spaghetti(cooked of course). It seem the only way to get this feeling in the arms is to disengage the shoulders. Uke always has the option to let go and escape the exercise, unless his mind has been captured in his grip by the person doing the 'proper' practice.
So I've made some sudden and very interesting progress but I'm clearly still missing something subtle.
So I still have something to find.
You and the rest of us David, keep searching.