Min, you are describing the excat thing we consider to be most important for Aikido in my studies, the very essence Sensei keeps talking abotu and demonstrating and I keep struglling to immerse to my body and mind:
1) they move continously;
and 2) they never "receive" a strike but always dictate the terms of engagement. While the uke may initiate (and even that's doubtful), nage does not wait for the atemi or grab to come to fruition on uke's terms.
The methody my Sensei taught me when talking of teaching Aikido, considers static grasp situations as the basic training tool intended at improving your technique, learning to phisicly feel the other and learning the basic distance for action (grasps of outstreched hands, not chokes and similar situations). We often refer to this stage as the Ju-Jutsu stage, since the technics in Aikido are common to other JuJutsu arts.
Once one has reached a certain basic level, he should progress to dynamic grabs - move before the grasp and learn to do it so the other will only feel you later. We then progress to strikes and again, one learns presenting an opening is an invitation to being struck there, e.g. if you wish to be hit in the head - lower your hands. One should neverstay in place or move in a predictable manner after the attack has decided on his intent, it is best to move between the intent and the actual attack movement (I have seen sensei do it with some success, but my presentages on my best awareness days are still low).
And then, you can start thinking on initiating your attacker intent and misleading him to attack as you wish and eter the trap. This is high level Aikido, wish I will get there in a few decades.