We have a lot of BB visitors and I always make them wear a very thin Pink Belt with bright, yellow fringe if they get on the mat.
It's simply because we may teach some slightly different details than they are used to seeing, so I think it's important that they wear a different belt.
It's in no way a sign of disrespect.
But if they refuse to wear it, well, the door is right there.
Funny guy.. don't you have a school within a mile of Kron's? You always seem to be bagging on him or talkiing about a 'friend' who trained at Kron's and it's never positive. Interesting. It's cool, we've had a couple of people come through who were at Tsunami and they didn't have positive things to say either.
FYI, it's not slight details, more like the philosophy behind his jiu-jitsu. Instead of just constantly talkin shit, maybe you could train with him and understand why the school is the way it is instead of assuming like you always do. I get it though, it's much easier to sit in front of a computer and jape.