I guess, upon rereading the whole thing, that the issue is that I don't think people should be upset if they mistake me for a different gender/race/whatever since I don't consider any subgroups to be worse than any others. And I don't correct misapprehensions along those lines, unless relevant to the conversation, because I don't think people should think that they are insulting people by putting them in the wrong bin, because again, bins are just different, and none ought to be considered worse than others.
However, I also realize that this is not a general attitude, since people, even some Mudcatters, ARE upset when they find out they were wrong. So my priorities become the question - is it more important to me to continue to practice nothing-ism and continue not to correct, and to reassure those who might worry about misidentifying that I was in no way insulted? Or do I put avoiding the worry above avoiding the isms? My tendency is to avoid the -ism rather than the worry as I do find it CRITICALLY IMPORTANT that people stop considering mistaken identity to be insulting. But I don't want to upset people I consider my friends, either. HELP! What to do?