Is this enough to avoid punishment for plagiarism?
Apparently. All ban appeals are judged on a case-by-case basis.
And what do you tell other banned users?
Usually that they're useless shitposters who never contributed anything to bitcointalk other than bounty spam and that they don't deserve to be unbanned. I'm sure you've read a lot of ban appeal threads.
Seems like someone is doing an outstanding job in finding out the plagiarists lately.
Hell yes, and I'm curious to know who that person is. Hilariousandco alluded to it being a member who ought to be a mod, but the member was never named. I have a short list of suspects, though. In any case, I think it's fantastic that his reports are being acted on.