Re: The Founder's Teaching Ability
A senior instructor in any large dojo or organization, especially as he or she ages, will tend to allow his senior students to do more of the teaching. His or her instruction shifts more towards creating good teachers who can carry on than teaching the basics him or her self. I don't think there is anything unusual about this.
So these discussions about whether O Sensei was a good teacher are proxy arguments for other assumptions. I look at the Aikido world and see good post-war Aikido in general (though I fear we are headed off course lately). Others see bad Aikido. Some think it was always bad. Others think it got worse after the war. If Aikido is bad the world over, then the assumption is that O Sensei failed to teach well by any measure of what teaching means. If Aikido is good, at least among his senior students, then the assumption is that O Sensei did manage to teach what needed teaching. This is what is really being discussed.