Yeesh. Step out for a couple days to work on your bodyhacking and there's a trench war going on when you get back...
In all seriousness, there seems to be a lot of shouting here. Intelligent shouting, mind you, but I am not sure how much of it is actually informative.
This looks like a pretty simple situation to run a cost/benefit on: will censoring of the sort proposed help, hurt, or have little appreciable effect on the community.
Benefits: May help public image. (Sub-benefits: Make LW more friendly to new persons, advance SIAI-related PR); May reduce brain-eating discussions (If I advocate violence against group X, even as a hypothetical, and you are a member of said group, then you have a vested political interest whether or not my initial idea was good which leads to worse discussion); May preserve what is essentially a community norm now (as many have noted) in the face of future change; Will remove one particularly noxious and bad-PR generating avenue for trolling. (Which won't remove trolling, of course. In fact, fighting trolls gives them attention, which they like: see Cons)
Costs: May increase bad PR for censoring (Rare in my experience, provided that the rules are sensibly enforced); May lead to people not posting important ideas for fear of violating rules (corollary: may help lead to environment where people post less); May create "silly" attempts to get around the rule by gray-areaing it (Where people say things like "I won't say which country, but it starts with United States and rhymes with Bymerica") which is a headache; May increase trolling (Trolls love it when there are rules to break, as these violations give them attention); May increase odds of LW community members acting in violence
Those are all the ones I could come up with in a few minutes after reading many posts. I am not sure what weights or probabilities to assign: probabilities could be determined by looking at other communities and incidents of media exposure, possibly comparing community size to exposure and total harm done and comparing that to a sample of similarly-sized communities. Maybe with a focus on communities about the size LW is now to cut down on the paperwork. Weights are trickier, but should probably be assigned in terms of expected harm to the community and its goals and the types of harm that could be done.
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.