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.
Nice. Makes sense too. Just goes to show it's more to do with respect than any words really.
Made me think of cultural differences too. Personally I like to immerse myself into the culture of something I am learning or doing. Made me recall a time I visited a famous Japanese teacher with a student. Whilst the student entered the dojo and proceeded to watch I stayed at the door. When he came back to enquire why I wasn't coming in I told him to just follow what I do. He did, the class stopped and a student was immediately sent to ask me to enter. Meanwhile, on visiting a friends class it was more him turning with a 'Yo.....what's happening dude?'