Rob Liberti wrote:
My opinion is that intermediate points of aikido are that you can avoid directly pushing, pulling, lifting, yanking, cranking (using sudden and jerky movements), threatening (with non-violence?!), and still be able to unfiy with the partner in such a way that they cannot do much about the overall movement because they are continueing to contribute to it. Higher than that, well, I think that you can do those thing (being true to principle) against people who are actively trying to resist you and hurt you. What do you think?
I think the unification is just a preliminary step in a technique. After that's accomplished, uke is there for you to do what you see as necessary--push, pull, twist, etc.
I reread your question about the significance of the heel...I previously ignored that it was a question about comparison. All of them are important, however, I think someone experienced with unification would have recognized what mentioning the heel signified. That's what the point of the original post was...not to say that one thing's less important than another.
One other thing, on the importance of the heel vs. ball of foot/toe. I think, in my desire to get to my point, I expressed under-estimation in the importance of the ball/toe. That's not the intent...more intended to say that power flow down a path. If your knee is the last point, then power will be fulcrumed there, if the heel is the last point, then from there.