From the biography of Shirata that I translated on Aikido Journal. As Shirata greeted a visitor asking for a lesson at the Kobukan, "A person who wishes to study aikido should start with the spirit. If the spirit is not correct, the path will also be incorrect." I translated kokoro as spirit in this instance, but you see heart, mind or self would work equally well with varying and valid nuance. Path is of course michi, the way.
Shirata had this kakemono hanging in the dojo to the end of his life: A person who is trying to study aikido must start by studying the spirit. Because if the spirit is not made righteous the path is not righteous either.
He obviously thought it was important like his teacher did. They taught that it wasn't enough to just become proficient physically.
Or as Dan has written here, "Aiki in me before aiki between me and thee."
That is why Dan is arguing on another thread about "spiritual aikido". It's all of a piece. You have to correct it all, correct your mind to correct your body, correct your body to correct your mind, same with spirit, same with the whole being; struggle, purify and produce change. They thought that you can't leave any part out and achieve a viable whole. "Create a new being with daily keiko." Create a new being and the quality of that being will show itself when it interacts with others.
That makes sense. It also clears up a lot of my confusion about Dan Harden's statements. His explanations in the other thread helped as well and seem in line with what you are saying here.
You have been most helpful. Thank you.