Not sure why the parent was downvoted.

"Arbitrary" and "random" tend to be used in different senses. "Random" connotes unpredictability, while "arbitrary" connotes subjectivity to individual judgement.

I was not intending to claim that the moderators' actions are based on rolling dice, for example.

And given the lack of policy, moderation power is necessarily exercised arbitrarily.

As I understand it, the word "arbitrary" refers to lack of relevant or systematic explanation or reason for something. I'm not sure what meaning you intend, the word is confusing the way you use it in this context. (Suppose hypothetically that the policy I stated above was more prominently stated previously.)

Basing any action on 30-day karma seems unfair in this case. There was a relatively short window during which the comments were being downvoted, and now they're banned; typically for a controversial topic, those would have been reversed by upvotes over the next week. I don't know if that would have happened in this case, but now we'll never know.

Plausible, not conclusive. It's an old enough user account to be more conservative on the odd chance that there is an alternative explanation. (Unbanned Incorrect in that thread so that others can judge, it's not that toxic on its own. As a result, there are currently no (recent) comments by Incorrect that are banned.)

I admire your restrain. I'm also really glad to see Alicorn taking the hands on approach to Will's disruptions. As a curious observer, and for whatever it is worth I'm approximately neutral with respect to the "Ban Incorrect" decision. I naturally agree that banning on suspicion is a potentially abhorrent heuristic. Justice systems are so much better when "beyond reasonable doubt" is applied. However in this case the mistake isn't banning someone who is innocent. It is banning someone who is acting like a willfully obnoxious fool who delights in baiting people for responses by saying stupid things in a way that looks like it could be Will Newsome. If the last part happens to be false then hey, at least Alicorn still got rid of comments by someone who was deliberately being an asshat.

Even when it results in false positives (people behaving like Will at his worst are banned as Will sockpuppets) or false negatives (Will acts like someone who isn't being a dick on one of his sockpuppets so isn't banned) the policy still results in Mission. Fucking. Acomplished.

Purely out of interest Alicorn, do you just ban individual comments by the supsected sockpuppets when they also happen to be silly comments? Or do you just ban all of them? The former option seems like more work but more power to you if you are willing to put in the effort. The latter option would be ok, but then it seems like you just need a 'ban account' feature instead!

Account age isn't a guarantee - I know Will has older accounts than his current main, although I haven't seen them in circulation recently - but I'll abide by your conservatism here.