Basically, the problem is that the idea of a general forum that attempts to apply no-holds-barred rational thinking to all sorts of sundry topics is unworkable.

What's scarier, the idea of a conceptual apparatus that attempts to apply no-holds-barred rational thinking to all sorts of sundry topics may to an extent be unworkable. If the deniers of high-status-falsehood-1 all started using some catchy phrase (of the sort that LW has lots of), and then the deniers of high-status-falsehood-2 started using that phrase too, both would start smelling like the other and seem crazier for it. (This is one of the considerations that make me not want to try getting around these restrictions with pseudonyms.) On the other hand, of course, there are a number of concepts to fall back on that basically can't be corrupted because they're used all the time by e.g. probability theorists obviously lacking any agenda.

I disagree, however, with your characterization of option (1) as "forgoing some minor novel insights on a topic that affects most people's life decisions only very indirectly."

When I said that, I was thinking of the "do women like nice guys or jerks" question specifically. I wouldn't say politically-charged topics hardly affect people's lives as a blanket statement, though I think it's true in a great many cases. But your reading was the more natural one and I apologize for being unclear.

It will either lead to people questioning

I object to your use of "questioning" here, because it has become ambiguous. I suppose you mean "espousing low-status opinions as the result of questioning".

ruthlessly principled policing of off-topic content

Notice how and why nothing like this has been necessary for traditional politics. People post political manifestos and are often told both that the content is inappropriate because of its subject and that they have made specific severe errors of thought. I don't remember a case in which the political poster kept pushing and ultimately only the first response was given, because it isn't really true, it's just that if content is political, the outside view is that it is flawed.

the idea of a general forum that attempts to apply no-holds-barred rational thinking to all sorts of sundry topics is unworkable.

The point of the forum is to develop thinking techniques that are useful because they can be widely applicable. Apolitical examples are part of the training, but eventually one only cares about applying the system of thought when it reaches correct conclusions that otherwise would not have been reached, and it will inevitably deviate from what other systems would conclude.

Allow me to float an idea: post a disclaimer on the site that as a test and to prevent cultishness, one (or perhaps a few) deceptively wrong idea (wrong as unanimously agreed upon by a number of demonstrably masterful people) is advocated as if it were the mainstream opinion here, and aspiring rationalists are expected to reach the unpopular (here) opinion. The masters - most,but not all of them - argue for the popular (here) opinion that is low-status in society. Anyone who objects that an aspect of the site has a plurality of evilly inclined and majority of wrongly thinking people on a topic (say, PUA) can be told that that subject is suspected to be the (or one of the) ones on which the best thinkers not only disagree with the local majority opinion, but do so unanimously.

It goes without saying that...well, it really does go without saying, so I won't say it.

There is plenty of low-hanging fruit in terms of insight from applying unbiased thinking to issues where the respectable opinion is severely delusional.

It's really hard to actually know when the "respectable" opinion is severely delusional... and even if the consensus view is indeed totally wrong, most minority opinions are usually even wronger than that. Saying the Sun orbits the Earth is much less crazy that saying that the Sun orbits the Moon half the time and Mars the other half of the time.

See also.

It seems to me that this topic falls squarely into the last category.

Since "women prefer jerks" is something which is commonly believed

I disagree insofar as it's not obvious what that phrase means.

Women are, on average, more attracted to men who are more selfish and aggressive than they are compliant and cooperative.

I don't find "do women dig jerks?" particularly mind-killing, or at least, not here (much less than the ethics of PUA, political parties, elections, welfare, taxes, Occupy Wall Street, race and intelligence, Israel and Palestine ...); I don't have strong opinions on the issue, and hearing someone speak on that topic doesn't allow me to categorize them into a clearly-defined group.

I can't clearly see any "sides" on the issue (two possible sides are of course "women are stupid and dig jerks so I hate them" and "anybody who criticizes women is stupid", but I'm not seeing either of those here, the sides are more "it's complicated" and "it's not that simple").

Why would anyone so disagree? If this topic isn't off-topic and mind-killing, is there any topic that is?

I would say yes. I mean, it's clearly on topic relative the main post, and if instrumental rationality is going to be one of the focuses of the site, then "on topic" for top level posts is necessarily going to be pretty broad.

As for mind-killing, there are certainly topics I think it's harder to hold a productive conversation on.