I read about a child porn guy on the dark web once, he was an auzzie I think. He always said some strange greeting on every post. He would say hiyas.

They found Facebook posts where some dude said hiyas, did some police work and got him.

Found an article: https://www.bbc.com/news/uk-36437856

This isn't quite the same, but validates the point you are making for sure.

In the process, you've established another identifiable pattern.

Well, the point is to keep that fingerprint isolated to anonymous accounts. I don't mind if anonymous accounts are linked. Luckily I don't write much outside HN, and even less under my real name. I am, however, not under the illusion that this practice makes me safe. It's just something I do out of nervousness, since the only other option is not to write, and I'd rather not give it up.

Yeah, you can't just change from one fingerprint to another - you either have to erase your fingerprint (such that you look identical to someone else), or generate random ones and cycle through them. The anti-web-tracking people have been wrestling with this one for a bit.