It's interesting to note that "SafeSpeeder" has suffered a more severe penalty than other banned users: Almost all of his posts have been removed, though they still survive to the extent other users quoted them (but the link to go to the quoted post won't work). Usually when a user is banned, the posts themselves remain.
I was more under the impression that the user pulled a “71” prior to the banhammer completing its swing & deleted the posts himself, as his actual post count decreased back to 15 and his post tier reverted to “Dirt Road” accordingly (whereas I’ve seen the mods explain elsewhere that when they “delete” posts, they simply move them to an invisible thread, which means post counts wouldn’t decrease like they did here).
His current profile shows only two posts. The lead post in the "Speed Kills Your Pocketbook" thread that ran off the rails, and a post in the "time dilation" thread.
His profile says he has 15, but only two are still visible, and it's easy enough to see why: Both of the posts are the first ones in their respective threads. I believe one of the moderators explained that technical restrictions prevent the deletion of the first post in a thread once there are any replies to it, unless the moderators choose to delete the entire thread. (I suppose they could split everything after the first post and then delete that post, but that would entail more work and would potentially take away relevant context.)
When I was reading the forum last night around the time when the post deletions began, I concluded the moderators were dealing with it because they split off a big chunk of the "driver's education" thread right as I was posting to it, then deleted the portion they'd split off. At that time, the rest of that user's posts were still around, so I just assumed it was the moderators getting rid of all of it.
Watch him come back with another new account in the next day or two...
As Max Rockatansky has noted, we seem to have a version of the hydra around here lately.