Why not just delete [most] offending comments, immediately, no questions asked (and ban repeat offenders)? For maybe 95% (as a wild guess), there's no question - it's clear that the comment is inflammatory or disinformation or whatever. It surprises me that I see so many of them permitted in so many forums, even here on HN. Why tolerate them? One click and move on.
Tell people about the policy, of course, and if the comment is partly offending and partly constructive, delete it. They can re-post the constructive part. It's not hard to behave - we all do it in social situations. If you want your comment to be retained, don't do stupid stuff.
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Also, it's telling IMHO that in this conversation among people relatively sophisticated in this issue, organized disinformation is barely discussed. It's well-known, well-documented, and common, yet we seem to close our eyes to it. It's a different kind of moderation challenge.