Re: Ukemi: pluses and minuses
Just one more for the "interesting quote" category. K. Asai, a contemporary of Kobayashi, related his first experiences in aikido, and said that his first lesson basically consisted of grabbing a senior's wrist (I believe the wrist belonged to Arikawa) and being thrown into the mat with a powerful iriminage.
I also recall an interview in the old Fighting Arts International with Chiba Sensei, who said that he already knew the breakfalls from his judo training. Maybe this is what he was implying - students weren't taught ukemi, they learned it as a survival method.
One more point - I believe the elder Ueshiba initially only accepted people with a martial arts background as students. Remember that even kendo had a footsweeps and iriminage-type throws, so in all likelihood all of the early students already had some experience in ukemi.