The freaky consequences are not of the policy, they're of the meta-policy. You know how communities die when they stop being fun? Occasional shitstorms are not fun, and fear of saying something that will cause a shitstorm is not fun. Benevolent dictators work well to keep communities fun; the justifications don't apply when the dictator is pursuing goals that aren't in the selfish interest of members and interested lurkers; making the institute the founder likes look bad only weakly impacts community fun.
Predictable consequences are bright iconoclasts leaving, and shitstorm frequency increasing. (That's kinda hard to settle: the former is imprecise and the latter can be rigged.)
Every time, people complain much less about the policy than about not being consulted. There are at least two metapolicies that avoid this:
Avoid kicking up shitstorms. In this particular instance, you could have told CronoDAS his post was stupid and suggest he delete it, and then said "Hey, everyone, let's stop talking about violence against specific people, it's stupid and makes us look bad" without putting your moderator hat on.
Produce a policy, possibly ridiculously stringent, that covers most things you don't like, which allows people to predict moderator behavior and doesn't change often. Ignore complaints when enforcing, and do what you wish with complaints on principle.
New proposed censorship policy:
Any post or comment which advocates or 'asks about' violence against sufficiently identifiable real people or groups (as opposed to aliens or hypothetical people on trolley tracks) may be deleted, along with replies that also contain the info necessary to visualize violence against real people.
Reason: Talking about such violence makes that violence more probable, and makes LW look bad; and numerous message boards across the Earth censor discussion of various subtypes of proposed criminal activity without anything bad happening to them.
More generally: Posts or comments advocating or 'asking about' violation of laws that are actually enforced against middle-class people (e.g., kidnapping, not anti-marijuana laws) may at the admins' option be censored on the grounds that it makes LW look bad and that anyone talking about a proposed crime on the Internet fails forever as a criminal (i.e., even if a proposed conspiratorial crime were in fact good, there would still be net negative expected utility from talking about it on the Internet; if it's a bad idea, promoting it conceptually by discussing it is also a bad idea; therefore and in full generality this is a low-value form of discussion).
This is not a poll, but I am asking in advance if anyone has non-obvious consequences they want to point out or policy considerations they would like to raise. In other words, the form of this discussion is not 'Do you like this?' - you probably have a different cost function from people who are held responsible for how LW looks as a whole - but rather, 'Are there any predictable consequences we didn't think of that you would like to point out, and possibly bet on with us if there's a good way to settle the bet?'
Yes, a post of this type was just recently made. I will not link to it, since this censorship policy implies that it will shortly be deleted, and reproducing the info necessary to say who was hypothetically targeted and why would be against the policy.