4chan is a shining example of the outright failure of anonymity on the internet shines a light on the discussion. That concept just introduces people who will argue completely in bad faith, have their argument taken down eloquently by a new user not realizing what is going on, the that same troll will just post the argument again, constantly. Real names are absolutely not necessary for a good discussion but social and structural consequences are very important in removing trolls.

HNs rule if allowing throwaway accounts for discussing sensitive content is a good thing, but I'd prefer some kind of linking to the main account to make it obvious that if you're making a green account you troll it will effect your main account as well.