I'm torn on this one. While I understand and agree with the idea of the title O-sensei as an honorific and a completely deserved one, I think I see where Ted is coming at with the literal translation of the word.
O-sensei means great teacher. From many of the things I've read Ueshiba really wasn't that great of a TEACHER, at least not by the modern sense of the word. He would demonstrate techniques and leave the students to puzzle out what he was doing. He would lecture on things his students themselves claim they couldn't understand. I've read on these very forums that some people attribute the growth of aikido not to Ueshiba's great ability as a teacher but to his followers great ability as students. It was the students who named the techniques to make learning them easier. They were the ones who figured out ways to actually TEACH it to somebody else, as opposed to just demonstrating and expecting the students to figure it out on their own.
Just my take on it.