Where I draw the line: I try not to deliberately offend without good reason. I am moderately careful to avoid accidentally offending, and if I misstep I think through what caused offense and decide whether I'll take care to avoid doing that again. Usually I will, but sometimes I won't. (Random example, I usually do not refrain from jokes about wildlife being potential dinner, even though I know some vegetarians who are offended at the concept.)

That said, reading through the thread, I personally find ptum's responses more offensive than DrHyde's initial comment. As the saying goes, be strict in what you emit and liberal in what you accept. Neither person followed that advice. However it seems to me that ptum was farther from that ideal. (That said, once DrHyde saw that this annoyed ptum, he shouldn't have prodded further...)