[NeedMoreTea]

At least a couple of newspaper comment sections, and forums have had pre-moderation for sensitive topics.

Nothing is visible until it's been validated. Guardian comments still do this for some topics.

With all the assorted profiling going on, I'm sure just as some users (like via Tor or VPN) are automatically given harder Google captchas, or some boards make you earn enough karma to perform certain actions, reactionary moderating could be something you have to earn, and sustain. Perhaps certain interests would trigger proactive moderating too.

Not perfect but certainly capable of taking much load off human moderators.