First your comment on good teacher doesn't equate with lot's of students. A teacher who starts a way and it spreads in such a way as Aikido did is actually a Great Teacher.
The main point though which I think you are referring to is my comment on what about if there is good?
It's not a joke, it's real. Whether a technique or move is good or not is not a matter conjecture or different expectations etc. It's a matter of honesty.
You know without a shadow of doubt when your application was good. The uke knows without a shadow of doubt when an application done is good. Those watching are quite irrelevant really.
I am not sure about that. Can everybody really detect openings in the technique?