Now would be a good time to re-read Well-Kept Gardens Die By Pacifism in its entirety.
I did. It was about how community should allow moderator to make decisions the moderator considers necessary to protect the community.
It wasn't about how one faction should use external criticism to create a new rule to exile an opposing faction. That would be more similar to Evaporative Cooling of Group Beliefs.
A few years back, I was on a transhumanist mailing list where a small group espousing "social democratic transhumanism" vitriolically insulted every libertarian on the list. Most libertarians left the mailing list, most of the others gave up on posting. As a result, the remaining group shifted substantially to the left. Was this deliberate? Probably not, because I don't think the perpetrators knew that much psychology. (For that matter, I can't recall seeing the evaporative cooling analogy elsewhere, though that doesn't mean it hasn't been noted before.) At most, they might have thought to make themselves "bigger fish in a smaller pond".
This is one reason why it's important to be prejudiced in favor of tolerating dissent. Wait until substantially after it seems to you justified in ejecting a member from the group, before actually ejecting. If you get rid of the old outliers, the group position will shift, and someone else will become the oddball. If you eject them too, you're well on the way to becoming a Bose-Einstein condensate and, er, exploding.
This back and forth is delightfully ironic given the micro-reactionary content of Well-Kept Gardens.
A long blog post explains why the author, a feminist, is not comfortable with the rationalist community despite thinking it is "super cool and interesting". It's directed specifically at Yvain, but it's probably general enough to be of some interest here.
http://apophemi.wordpress.com/2014/01/04/why-im-not-on-the-rationalist-masterlist/
I'm not sure if I can summarize this fairly but the main thrust seems to be that we are overly willing to entertain offensive/taboo/hurtful ideas and this drives off many types of people. Here's a quote:
The author perceives a link between LW type open discourse and danger to minority groups. I'm not sure whether that's true or not. Take race. Many LWers are willing to entertain ideas about the existence and possible importance of average group differences in psychological traits. So, maybe LWers are racists. But they're racists who continually obsess over optimizing their philanthropic contributions to African charities. So, maybe not racists in a dangerous way?
An overly rosy view, perhaps, and I don't want to deny the reality of the blogger's experience. Clearly, the person is intelligent and attracted to some aspects of LW discourse while turned off by other aspects.