While there are benefits to that sort of aggressive division, there are also costs. Many conversations move smoothly between many different topics, and either they stay on one side (vitiating the entire reason for a split), or people yell and scream to get them moved, being a huge pain in the ass and making it much harder to have these conversations.

I realize that it says "a community blog devoted to refining the art of human rationality" at the top of every page here, but it often seems that people here are interested in "a community blog for topics which people who are devoted to refining the art of human rationality are interested in," which is not really in conflict at all with (what I presume is) LW's mission of fostering the growth of a rationality community.

I've seen exactly this pattern before at SF conventions. At the last Eastercon (the largest annual British SF convention) there was some criticism that the programme contained too many items that had nothing to do with SF, however broadly defined. Instead, they were items of interest to (some of) the sort of people who go to the Eastercon.

A certain amount of that sort of thing is ok, but if there's too much it loses the focus, the reason for the conversational venue to exist. Given that there are already thriving forums such as agi and sl4, discussing their topics here is out of place unless there is some specific rationality relevance. As a rule of thumb, I suggest that off-topic discussions be confined to the Open Threads.

If there's the demand, LessLessWrong might be useful. Cf. rec.arts.sf.fandom, the newsgroup for discussing anything of interest to the sort of people who participate in rec.arts.sf.fandom, the other rec.arts.sf.* newsgroups being for specific SF-related subjects.

(A good solution is maybe dividing LW into two sub-sites: Less Wrong, for the purist posts on rationality, and Less Less Wrong, for casual ("off-topic") discussion of rationality.)

Better yet, we could call them Overcoming Bias and Less Wrong, respectively.