Re: Effective udekimenage against resistance
Hi Reuben, just from a theoretical point of view: one thing has to happen to make it require a roll as opposed to just a walking/jogging/hopping forward projection. That one thing is that the top of the body has to get accelerated forward, while the legs/bottom of body gets a lot less forward acceleration (or even gets acceleration in the opposite direction).
You pointed out one way to make this happen-- stop the uke's legs with your hip or your leg. Extreme version of this is judo-like throws or turning this into koshi nage.
In terms of basic mechanics of making it a throw instead of a forward shove or an "elbow attack," that will do it.
Another way to do this same top/bottom trick would be to manipulate the sensation of weight so that he can't step forward easily-- so there is some difficulty stepping, all the while his upper body is getting a lot of acceleration. I think the way to practice that is the common exercises of lifting (kokyu dosa or aiki age) as well as doing tai-no-henko with a sinking feeling. Still working on that. But neither of these threaten the elbow, it is just lifting and sinking, in ways that affect where and when he can easily step. So now when you go back to udekimenage, then you have something that is independent of the elbow.
Another way to get the legs moving kind of backward while you take the upper body forward would be a wave motion, maybe something to combine with the above method. In other words go back-then-forward, timed with the wave action in his body (this may be best with soft, flexible ukes), so that the legs are still experiencing "backward," while you have begun driving the "forward" upstairs.
Well, it's a forum so take this with a grain of salt! If I make a video or something then my "theories" can have more credence.