Hi John - thanks for your view on things.
I think the big question about this kind of practice is whether repeating it again and again will get you there. People like Dan and Mike talk all the time about the need for regular solo practice to develop these "lines" internally (and Kanetsuka Sensei among others keeps hinting at this too), but Ikeda Sensei didn't talk much about this aspect at all - not in the classes I was in, at least .
I think he demonstrated quite a few exercises over the weekend, the ball things he does (looks like he's body popping), the shifting, the moving inside / wave kind of exercise... All of those can be done solo like he said and with a wall or a solid partner to get the hang of them.
One of the things I like about Ikeda sensei is if you don't get something, ask him, he'll usually give you some ideas to work on
Have to say I felt a large range of people from all sorts of backgrounds and a lot of people were convinced this is what they do anyway... It's the same thing... ahhhh, we do this... I didn't get to feel so many people with a good, well connected body if I'm being honest (from an uke's point of view). Most people were moving from forearm and shoulder, I felt little coming from people's centers... But then, isn't that the point of all this? We can go back and try.