Oisin O'brien Bourke
It's also impossible to verify. Sagawa never had a good word to say about anyone, apart from himself. Using sagawa as an reference for anything basically renders the claim invalid as, according to sagawa, no-one got the super duper secret aiki (TM) except sagawa. In fairness to him, he wasn't splashing himself all over the internet boasting about it.
Oh, I don't know..
But I agree that it is nearly impossible to verify.
As I understood, he supposed, that you never could say, wether your Aiki was the same as someone else's, because of the nature of Aiki. He apparently told Kimura, that he weren't sure about this sameness in the case of him and his venerated teacher. But he didn't exclude that someone could reach the same level as his own, that's probably why he trained to the last day….
...very much like many others.
And here everyone may name his preferred figurehead.
In our quest for final historical accuracy, we may be doomed to fail, though at least a few of us have brought a shimmer of light into the world of contemporary budo, and this in an entertaining way....