when he's talking about what he could do, which the head of your lineage (along with many other skilled men) felt and wanted to be able to do himself and what I assume you're doing some approximation of today, then it's probably safe to say that yes, he is right. Just because you don't understand it, can't do it and seemingly aren't interested in it doesn't make him any less right.
So you do understand it? I always felt it is pertinent to have a inquisitive mind and not to accept everything just 'cause someone says so.....
I'm not doubting Proff Ueshibas ability, but I also recognise that there are just as good martial artist as he was that are/were around even to this day.... not just in aikido..... Proff Ueshiba cross trained and really came up with his own eclectic system, based heavily on Daito Ryu, that there can be no doubt of. Takeda was an excellent all round martial artist who took on all comers and really proved his worth, why can't we? He experimented/fought even to the risk of his own life, have you?
I know I have to some extent.... I don't pretend to be the best, nor am I the worst, but I prefer reality to just heresay.... Not just hope it works.... If I wasn't interested in it I would not bother to train which I still do most days, even though I do not have a dojo at present.... I think it's more about searching within oneself, not hoping to do what others do and just copying which is what we all do in the beginning as we all have to do, learn the basics for at least ten years of regular solid practise. If we cannot develop from that we are
wasting our time don't you think?