“Hellbanning” is becoming so ubiquitous (particularly on newspaper sites…) that aspiring trolls have already found the obvious solution; simply create a “stealth” account to check and see if they can view their posts from the “troll” account from time to time.
Got banned? Can’t see your posts? Create new troll account. Laugh at moderators; “Ha, ha - you so smart.”
This tactic also works perfectly well against “errorbanning” and “slowbanning.” Simply check using the stealth account. No errors? Site working fine? Time for a new troll account!
What I think more (any?) sites should do is revive an ancient concept - the killfile. Let the users themselves decide who they don’t want to hear from any more, on an individual basis. Point at a troll’s post, press the “Killfile” button, and you - just you - don’t see any posts from this guy again. This allows maximum flexibility and puts each user in charge of his online experience.
This amounts to a personal-basis hellbanning. The troll vanishes from the radar of each user who finds him annoying - yet his posts remain. All he knows is that apparently no one feels the need to respond to him any longer … and the few newbies who do respond aren’t providing enough fodder for his ego. He rides off into the sunset.