"When O-Sensei's student ask him why is it that they cannot do what he does, his answer was "you do not understand Aikido".
This sounds like a familiar quote of Henry Kono. I have come across this quote on Aiki web before, but it was a little bit different (shows how a story at times develops into something else entirely, a bit like with urban myths).
I met Henry Kono the first time in 2000, when I had invited him to come over and give a weekend seminar in the Netherlands. During class he told the story how one day he decided to ask O Sensei a question that was in his mind for quite a while. He had seen what O Sensei did and he had looked carefully at what his students (including himself) did and to him it was not the same thing. So he asked O Sensei "Why can't we do what you can do?" O Sensei answered him; "Because you do not understand Yin and Yang". After class in a private conversation with Henry I questioned this remark by O Sensei. And Henry Kono told me; "Yes, you are right, he did not use the words Yin and Yang. In reality O Sensei told me that we could not do what he did because we did not understand Izanagi and Izanami. But most people do not understand this. So I simplified it into Yin and Yang". And this is how he still explains it in his seminars and on his dvd's.
Yin and Yang can be compared to Izanagi and Izanami. But it is not exactly the same.
As far as transmitting knowledge is concerned, a good student does not depend on explanations, sometimes simply hinting at the right direction will do.
Interesting - what would you say are the differences between Yin and Yang and Izanagi and Izanami (as Ueshiba used the terms here)?
Hinting at the right direction is a common Japanese methodology - but if you look at the results it really doesn't work very well, even in Japan. In the mass teaching environment of Aikido I would say that it works...not at all, really...