Something we worked on just this weekend:
same side wrist grab, partner grabbing and pushing to see if your shoulder collapses up/in/back/whatever, so you can be pushed back. Or whether you can keep your structure while being pushed.
Once that was established (to some reasonable degree
), starting a tenkan movement (still being grabbed). Partner would say if they felt anything change in the arm being grabbed. That meant tensing up which gave partner something to hold on to which made it easy to counter or just stop the movement.
Managed a couple tenkans where I could maintain my own structure and my partner didn't feel anything change during the movement. (Woohoo!)
Obviously you do need a training partner who knows what to feel for.
You can do the same obviously with any kata, that is you can check 1. if your structure holds at the moment of contact or if your uke can disrupt it at that moment 2. whether or not you can keep that same structure going continuously from that moment on without your uke feeling a change.
What I find difficult personally is if the point of contact isn't on an arm (like with most aikido attacks) but on my torso or shoulder (katadori or eridori attacks, that kind of thing).