Is your contention that in the absence of any rule on the subject people would tend to self-censor spoilers (even this one, out of all spoilers)
The rule on Less Wrong aside from HP:MOR threads is that you shouldn’t spoil anything unless you’re really sure it’s common knowledge, and anyone claiming it’s not common knowledge is usually good enough evidence that it’s not common knowledge. So you can say “C3P0 is Luke Skywalker’s father” in a post about rationality, but if anyone complains then it should probably be changed to “Spoiler for Empire Strikes Back (ROT13): blahblahblah”, and “last week’s episode of Buffy” should always be concealed.
This rule is directly enforced by Eliezer when necessary; he is very anti-spoilers. Unfortunately, I don’t think the policy is stated directly anywhere other than here.
The rule on Less Wrong aside from HP:MOR threads is that you shouldn’t spoil anything unless you’re really sure it’s common knowledge, and anyone claiming it’s not common knowledge is usually good enough evidence that it’s not common knowledge. So you can say “C3P0 is Luke Skywalker’s father” in a post about rationality, but if anyone complains then it should probably be changed to “Spoiler for Empire Strikes Back (ROT13): blahblahblah”, and “last week’s episode of Buffy” should always be concealed.
This rule is directly enforced by Eliezer when necessary; he is very anti-spoilers. Unfortunately, I don’t think the policy is stated directly anywhere other than here.