Check Out This Tiny Circle
Often times we can off balance by making our uke move in a circle. This is part of what my perception of what NSA seems to be noodling around with. They are looking to create that moment of kazushi. They are keeping this thought in mind as they practice. It's one thing to do this subconsciously and another to create the moment purposefully to help understand it.
The whole video is awesome but watch at 7:13 seconds in. Endo Sensei moves uke in a really small circle. It's so small, that I doubt I would have noticed it a couple years ago. It looks like he moves in and then out with his whole center to accomplish the throw.