Is suspect this is a required transition. The next question is what else did you have to have to get there?
Consistent, specific practice working to fix specific things largely in myself, my posture, my movement, my 'innate' (and incorrect) assumptions about what works or how stuff works and working by replacing the recognition of what NOT to do with something very specific TO do.
It doesn't work well to tell yourself NOT to do something.. Like with target fixation, your body executes the images of what it fixates on, so you have to replace that image.
Hilary, I really liked your post. One point you touched on, I have also heard from some that I should move like no one is there, that Aiki body is something separate and distinct from a relationship, and that the uke should be irrelevant. I cannot reconcile this idea with finding kuzushi, which is definitely my preference. I am a nurse; my work life is very much about paying attention to the other person. I approach a number of techniques as though I am half of the equation, or that I am the artist and uke is the clay.
They are not unrelated. Kuzushi in your partner is a natural consequence of moving like no one is there.
Another way to think about it, IME, is that what most people do when they are grabbed (or pushed or whatever) is engage responses that are not always ideal for dealing with being grabbed.
If one was paying attention to operating their body an an imperturbable manner until it became the natural way to move, they might encounter unusual, but daily situations such as that often used image of pushing open a door right when someone pulls from the other side and not losing your balance at all, or someone bumping into you losing their balance and falling or nearly falling while your posture is completely undisturbed.
So it's not that uke is irrelevant, it's that what they do should be irrelevant.. until it's not because you are connected. It's more that the relevance is usually something that people aren't accustomed to doing or feeling and the reaction they usually have when guided into correct movement is that it doesn't "feel" like they are doing anything to uke (but uke does not have that same feeling). I think it's why it's so easy to miss, because until you've been doing it for a while, that is exactly what it feels like.
I think I digress, but it's working on specific things like this for long enough that the desire to 'win' goes away that I become able to be more successful. One of the more amusing koan's I've encountered in life.