Your post has sobered me, but maybe it's for the best. I resolve never to try to "race" others in any sort of setting where competitive feelings may encourage them to take risks, e.g. anywhere around intersections.

There have been times in the past in which I've actively avoided passing other cyclists. I just turn onto a sidestreet so I'm not going by them. I want to avoid them feeling annoyed at being passed or getting drawn into some sort of race that I know they'll lose.

One other thing I have done along those lines is purposefully give another cyclist a huge head start and then chase them down to the point where I'm getting close, but they aren't aware of me yet. Then I brake and ride very slowly for a minute to give them a huge lead on me and do it again. I get the competitive fun, nobody gets irritated at being passed. Maybe that's what I'll have to start doing again.