Re: Watch Out for Aikido 'Shihans'..........
A useful question for instructors is "How do you feel about your students attending seminars outside your school?"
If they say, "That's fine" or "That will be fine once your ukemi skills are up to it, but not initially" those are reassuring answers. If they rant about how bad other teachers are, that's not. You'll have to make up your own mind about "I don't encourage mixing of styles" but I personally find that response disturbing. It can serve as a screen for "I don't dare allow you to compare my aikido with anyone else's."
I am very comfortable with my style and association in part because I've been able to train at a variety of other schools, and I know that what I'm being taught holds up. I can't always make things work (I wouldn't be a kyu rank if I could) but I don't feel myself to be at a disadvantage in learning compared to rankmates elsewhere. And I am still comfortable with my teachers' aikido and teaching, having compared them with some of the best people around.