Finally got around to reading this, which is another very interesting translation. Thanks Mr. Li!
This part struck me:
A: That's right. At least, of those who were actually able to use Aiki, there were only Takeda Sensei and Sagawa Sensei. If it's just form then there are many people who are doing it, but there were only two who were able to apply it when an opponent came to attack in earnest.
With respect to "opponents" "attacking in earnest," I wonder which of these he means:
1) an open, unrehearsed, free attack of any kind, or
2) the uke in a paired kata performing the pre-arranged attack with all of his might.
I figure it probably means 1), though it COULD conceivably mean 2) as you have translated it into English (perhaps in original Japanese as well, I don't know and might not ever).
To me, it sounds as though Kimura is saying that the application of aiki in the context of a kata is not that difficult, and not a particularly uncommon ability.
But then the transition to an ability to apply aiki freely, in an unrehearsed situation - is not itself aiki. Rather, its a different skill, or set of skills.