Re: What is "Aikido"?
I'm sorry, but I too am withdrawing from this conversation. Nothing personal. I think Erick's general theory has merit, but it misses the point. Personally, I think rotational dynamics and gyrations are way off the mark.
As far as understanding kuzushi no heiho, it's all about lines, angles, directions in which balance can be affected, and leverage. It has very little to do with rotational movement in the sense that Erick is talking about - gyro-oscillation. True a very large circle can appear linear. And also true that you can augment linear force with pivoting and spiraling motions, but generally the idea is to put the force in a straight line into the opponent. i.e. even if rotational movement/torque is involved, it is always converted to linear force at some point - e.g. using torque to create leverage to unbalance.
How else do wheels, catapults, slingshots, screwdrivers etc. work?
Feel free to PM me if you like.