Re: Strength vs Ki.
I wonder why I never hear any discussion on Toheis five principles of Aikido rather than the four principles of mind and body unification?
I conclude that many think that those four are the sum of his understanding.
Each of the five principles go as deep as you want them to go and take years to appreciate.
As a discipline his rules are more like a super discipline, a point missed by the majority unfortunately. That doesn't mean the way of teaching couldn't be improved by someone but merely that in terms of 'old school' well you can't get more old school than that.
This is why many don't last, impatience, the grass being greener on the other side, the usual story for most styles.