Well, yes. You're defining this yourself: LessWrong is about "settled issues" of science, and therefore it's okay to dismiss debate as a "waste of time and effort". Unitarian Universalists are about significantly more arbitrary positions, and therefore there's a lot more room for discussion, because people have different starting assumptions and/or goals.

No, Less Wrong isn't about settled issues, but they do come up fairly often in the course of relevant discussions. Separate magisteria arguments fail because they imply that consensus can be found based on different standards of evidence for different areas of discussion. Every area needs to be held to the same standard.

If you take the starting assumptions of the UUs as a given, then most of their stances are settled issues where questioning is a waste of time and effort. You can still have some really interesting discussions on corner cases and implementations, since the world is very chaotic and no one has yet managed to arrange a control group for controlled study :)

I'm not sure what the UU starting assumptions are. However, it seems unlikely that they are only terminal values, so standards of evidence should apply.

What evidence, exactly, do you have that Unitarian Universalists declare things 'heretical' significantly more often than LessWrong does?

The point of the first post that I made in this chain is that coming to a consensus based on overwhelming evidence is not the same as declaring something heretical.

You seem to be pursuing two lines of argument. In some places you're just asserting that UU does not have dogmatic elements, in contradiction to Vladimir_M's observations. That's a separate conversation, and not really my concern.

In other places, though, you're asserting that LW does have dogmatic elements. I have two problems with this. First, it's not accurate, as I've explained. Second, taking the two lines of argument together, it sounds like you're saying "UU doesn't have dogma... and anyway, LW does too!" The two clearly aren't consistent, so which is it?

Just to be clear, my main point is that LW doesn't have dogma or declare things heretical, not that UU does (although I think it might approach those things in some areas). For that point, I'm providing examples and descriptions of the difference between consensus based on overwhelming evidence and arbitrary dogma. Dogma is arbitrarily absolute; it's something to be questioned under no circumstances. Consensus based on evidence is a matter of Bayesian updating.

An unchallenged consensus on positions of social policy, which are complicated and generally do not have conclusive evidence on one side of an argument, indicates the existence of some reinforcing social mores.

Edit: the comment at which this reply was directed was significantly altered after I typed this reply. Please hold on while I attempt to catch up.