Re: What's in a name? sensei, shihan, etc.
Graham asked, " I'm also interested if some teacher who says 'call me John' gets upset when a respectful student calls him Sensei."
Since I'm a John, I'll answer... nope. The student who calls me sensei as a habit/practice is an ex-milatary career guy (Coast Guard) so maybe that's his reason, I don't know. Doesn't bother me, though it has made other students uncomfortable, when they've been calling me by my first name, and here he comes in with a more-formal Sensei. Makes them feel slightly itchy.
The ones who think "that way" about respect and showing respect tend to use "sir," or "Ma'am," in my experience. The ones who don't think "that way" about speaking/showing respect in that spoken fashion tend to not use names on the mat all, except perhaps to the training partner of the moment. The respect is there however, it is palpable.
My experience, anyway.