@DanielFischer Would this possibly be the user who confessed to multiple accounts, and beating the "MSE" system by exploiting some "bug"? math.stackexchange.com/users/550675/pompelle Because they are behaving much like they did prior to the deletion of at least one of their accounts.

Perhaps the user formerly known as user545963 (at least that was the id ascribed to the user)?

@amWhy Looking into it. Thanks for the heads-up.

I mention it because they often come to downvoted answers, sometimes even after their closure, to answer in the comments (like using 5 comments to answer a question.) After commenting here (immediately above), they came appeared here, answering in a comment, and then addressing me in a manner that reveals someone who's been around much longer than 4 days.

@DanielFischer Thanks!

@amWhy In contrast to a certain ex-user, you're welcome.

@DanielFischer :-)

@DanielFischer Is there any means, on SE, to blacklist an IP address from which many spurious accounts are created? Or is the match-up mainly a discovered by matches in the given email address of the account(s)?

@amWhy IP addresses can be blocked (needs an employee of course). But blocking a university is an extreme measure for extreme circumstances.

@DanielFischer True... when an institution/university IP is involved, I can understand that. But when is a pattern from deleted user accounts, as in the case above, tested, or checked for an IP address? to even know if it's a consumer pc/smartphone, or an institutional IP address?

Of course, these questions just come from a frustration of seeming always to be one (or more) steps behind chronic account creators whose earlier accounts have been deleted. And they may not even be answerable (as in I'm not seeking to know the secret workings of SE investigations).

scratches head Hum, we look at stuff when we have a reason to look at stuff.

I get it. It just really gets really discouraging to repeatedly encounter the user under a different guise. And repeatedly flag or comment here, and receive a short-term solution, only to have them reappear with another account. I just wish there were longer-term solutions.

Well, @DanielFischer In your part of the world, methinks it's getting pretty late! Thanks again for your help with handling user with revolving accounts today!