I know it's wrong to speak ill of the dead

But can anyone tell me what happened to Grimhacker?

One day he was on every other post spouting his special brand of unpleasantness, and the next thing I knew he was banned.

Was there one final straw post or did someone simply decide that he was a noxious presence and one sick puppy and mercifuly have him put to sleep?

He let enough info slip to identify himself as a previously-banned troll. Banned people are not allowed to re-introduce themselves, so once the ID was confirmed, he was nailed.

Just a clarification - if a banned poster comes back and cleans his act up he will not be re-banned, even if his previous identity is known. It’s only when a troll comes back with a new identity and continues to act like a jerk like he did before that he will be banned as soon as his identity is established.

This is true. Happened to me. One (inadvertant) mistake, one apology, one unbanned poster.

Grimhacker, in case you were wondering, was concrete. And Jebus. And Goddess knows how many more names.