Aikido, as a form of physically interactive exercise, truly is unique among the martial arts. It's truly dance like in its cadence and movement, and really, far more interesting to watch, with a wider gamut of appreciation while doing so, than most martial arts. It's understandable why its aesthetics, and the many positive nuances of the collaboration between a given pair of training partners that generate them, attract so many people to the art.
I was always enthralled by this type of movement: in particular, Aikido's trademark re-directions of the uke -- often with the uke moving in large circles around nage or in concert with nage's tenkan. Entralled, that is, until the first time I took ukemi when sampling Aikido. Because jujutsu/aiki-jujutsu techniques largely motivate the uke to respond in a linear fashion and drop the uke with little fanfare (for example, compare Daito-ryu Ippon-Dori
to Ikkyo), and that's what I'm used to and what generally is practical when dealing with varying levels of resistance in paired training, I found myself naturally peeling away from the nage vs. staying with him/her when taking ukemi. So, one has to consciously take steps in a wide circle to not come apart from the nage. After all, centrifugal force is what naturally occurs when an object is swung in an arc. I'd always understood that waza in modern Aikido require the uke to cooperate, which is true of doing waza in any Japanese martial art, but in most jujutsu there is relatively little footwork on the part of the uke once first contact occurs, so even the most cooperative practice doesn't require conscious stepping by the uke from that point forward in the technique.
However, since certain modern IP/IS adepts, e.g. Dan Harden, can motivate the uke, who's actively, fully resisting at the point(s) of contact, to involuntarily move with haste in one direction then be re-directed to involuntarily reverse his/her stepping into a wide arc, all the while maintaining a centripetal adhesion to the nage, I'm inclined to believe that Morihei Ueshiba and his well-regarded Daito-ryu contemporaries could do so as well.
Can the large, redirecting, circular movements of the uke in Aikido be accomplished without cooperative footwork by the uke or without the IP/IS body skills developed through methods of training advocated by those like Dan and Ark? If so, how? If you feel Morihei Ueshiba had something else in play to deal with the dojo-stormers of the early 20th century, then please feel free to offer up your thoughts.
For what it's worth, I can't adequately explain how fure-aiki cancels the uke's resistive force while simultaneously imparting what appears to be centripetal force: the overly simplified answer that will perturb the skeptics is that the tangental responses that consciously and unconsciously address the uke's force and positioning allow both conditions to occur. What I do know is, I've been the uke who's experienced it, and have peeled myself off the mat a number of times marveling that it's possible.
In a way, I'm saying that being able to pull off Aikido waza against a resisting uke requires a degree of competency with aiki that goes beyond what's typically needed in other arts, because of the degree to which the uke must be moved
within the course of a given technique.
My admiration for Aikido is at an all-time high.