Cady - You missed a small point. Ueshiba was anything but humble. I was thinking, for example, of Horikawa Kodo, whom, I may be mistaken, was more content to till his own fields.
The idea that Ueshiba was vulnerable to any pressure from Daito-ryu schools is inconceivably to me. He may have had it/escaped from Takeda in his latter years, but I doubt very much that anyone among his peers or juniors would have had any say in the matter whatsoever.
Finally, Ueshiba and Takeda broke with each other (or ueshiba left town) in the late 1930's. Sagawa was dispatched by Takeda only a few years earlier to ascertain that he was alright in the second Omotokyo incident. Tokimune used to visit "Ueshiba sensei," as he called him in the 1950's. Maybe he, like Kondo, was shown "what Takeda sensei taught me." (Referring to Kondo's account of UEshiba snatching up a jo and projecting him all over the place in what was to him incredible fashion.).
Maybe Tokimune's Daito-ryu has an element of things he learned from Ueshiba - it's surely as plausible as the idea that Shioda learned the real goodies from Horikawa.
So, really, all I think happened is that ueshiba's own creative direction diverged from his teacher, but they remained in contact for many years after this divergence - which was a mark of their closeness and also would engender friction. The very last few years of Takeda's life, alone, were devoid of contact, apparently.
Also, on another matter. I recently viewed a video of myself and compared it to a video of my instructor in Araki-ryu. It's remarkable how deeply imprinted his movement signature is on me. He NEVER told me how to move. I just paid attention. HIS teachers usually taught him a kata once. He'd be working out on the side, two of the old men would get together, and say, "Hey watch this." Do a kata once, and he'd never see it again, but he was responsible for knowing it impeccably.
That UEshiba allegedly didn't explicitly instruct after the war means little in my opinion. Perhaps the students, bored and distracted from the "god stuff" weren't paying attention when he showed exactly what to do.