Oh grr, the above comment was me, not logged in. I thought there was a way to edit that, but I can't remember how.
Hi Sue. If you submit when not logged in, you can click the "more" button on the right hand side of your post and that will give you an 'edit' option.
Thanks Bodnotbod. But when I edit the post, it doesn't change my IP to my username, it just annotates the post as "edited by other users." I don't really care that my IP is visible, but now I am intrigued/irked :-)
Reattributing an edit requires either asking a developer to do it, or telling me and having me oversight it, and then re-posting it from the correct username. Neither of those is easy/scalable, but I will oversight at request to protect someone's IP. Luckily, most people just sort of shrug and move on, as Sue did. :)