#changing it back would break all the links and cuts i've made under this username

[coquelicoq]

*whispers* howdy i'm afraid I have been summoned again by one of your "ask me bout/why" so please, why do you tag "not anon" instead of the username?

two reasons:

i'm thinking about the tag from the perspective of my primary audience, i.e., future me. future me is someday going to want to find this post (let's assume). what sorts of things will future me remember about this post that could help me find it? i'll remember it was an ask. i'll likely remember if it was sent on or off anon, but if it was sent off anon, i may or may not remember who exactly sent it, so tagging the username might not be that useful to me as an indexing tag. tagging an ask #anon or #not anon (as opposed to only tagging it #asks) means future me can find it about two times faster than if i had to look through all asks. the balance is between having specific enough tags that if i need to find a post it won't take forever to go back through that tag, and having general enough tags that it's not too hard for future me to guess which one current me might have used. i get asks from enough different people, and the number of asks i receive from each individual person is low enough, that giving each person their own indexing tag would be inefficient overall (time t1 to find a given post within the tag would decrease, but time t2 to figure out which tag to look in would increase, and t1 is already low enough that it's not worth the memory-cost of maintaining and retrieving dozens of different subtags).

i had my original username for about five years. my then-bf did not have a tumblr but knew my username and would sometimes look at my blog. when we broke up, i didn't want him to be able to find my blog anymore, so i changed my username. at some point after that, tumblr changed the way asker and poster usernames were displayed (it used to always retain the username as it appeared at the time of posting, regardless of whatever that user's current name was; after the update, it displayed the current name). i did a search within tumblr to see if there was still anything connected to my old username and found some asks i had sent people during those five years that they had tagged with my old username. the problem was that my new username was displaying in the ask itself, such that if you did a search on my old username, you would immediately learn the new one. this defeated the purpose of changing my username at all lol. so ever since then i've been more careful about when i use people's actual usernames because they're searchable within the body or tags of posts, and people may not always want to show up in searches. it can't always be helped, but at least when it comes to answering asks, not tagging the asker's username is very easy and costs me nothing. but tbh i'm mostly driven by resentment here (so upset i gave up my old username for NOTHING) rather than logic (pointless to apply logic to this situation because i can't be redoing my tagging system every time tumblr changes how searching works and/or how usernames display).