Rationality isn't just about knowing about things like Bayes's Theorem. It's also about:
* Saying oops and changing your mind occasionally.
* Knowing that clever arguing isn't the same as looking for truth.
* Actually paying attention to what succeeds and what fails, instead of just being driven by your internal theories.
* Reserving your self-congratulations for the occasions when you actually change a policy or belief, because while not every change is an improvement, every improvement is a change.
* Self-awareness - a core rational skill, but at the same time, a caterpillar that spent all day obsessing about being a caterpillar would never become a butterfly. . . .
* Asking whether your most cherished beliefs to shout about actually control your anticipations, whether they mean anything, never mind whether their predictions are actually correct.
* Understanding that correspondence bias means that most of your enemies are not inherently evil mutants but rather people who live in a different perceived world than you do. (Albeit of course that some people are selfish bastards and a very few of them are psychopaths.)
* Being able to accept and consider advice from other people who think you're doing something stupid, without lashing out at them; and the more you show them this is true, and the more they can trust you not to be offended if they're frank with you, the better the advice you can get. (Yes, this has a failure mode where insulting other people becomes a status display. But you can also have too much politeness, and it is a traditional strength of rationalists that they sometimes tell each other the truth. Now and then I've told college students that they are emitting terrible body odors, and the reply I usually get is that they had no idea and I am the first person ever to suggest this to them.)
* Comprehending the nontechnical arguments for Aumann's Agreement Theorem well enough to realize that when two people have common knowledge of a persistent disagreement, something is wrong somewhere - not that you can necessarily do better by automatically agreeing with everyone who persistently disagrees with you; but still, knowing that ideal rational agents wouldn't just go around yelling at each other all the time.
* Knowing about scope insensitivity and diminishing marginal returns doesn't just mean that you donate charitable dollars to "existential risks that few other people are working on", instead of "The Society For Curing Rare Diseases In Cute Puppies". It means you know that eating half a chocolate brownie appears as essentially the same pleasurable memory in retrospect as eating a whole brownie, so long as the other half isn't in front of you and you don't have the unpleasant memory of exerting willpower not to eat it. (Seriously, I didn't emphasize all the practical applications of every cognitive bias in the Less Wrong sequences but there are a lot of things like that.)
* The ability to dissent from conformity; realizing the difficulty and importance of being the first to dissent.
* Knowing that to avoid pluralistic ignorance everyone should write down their opinion on a sheet of paper before hearing what everyone else thinks.
Boil it down and you get something pretty admirable. They are trying to gather people who believe that it is possible for sincerity and reality bounded civil discourse ot produce a better world, and also are committed to the notion that particating in this discourse and taking it seriously can help the participants live better lives.
The Less Wrongians are not ivory tower philosophers arguing over how many angels you can fit on a pinhead. They recognize the importance of insuring that discussions about important ideas are grounded, while also recognizing that fitting reality into a theoretical construct is an unavoidable and non-trivial exercise that needs to be done right for the rest to hold together with any rigor.
Following that methodology, another recent study notes that one important way to reduce prejudice against those who do not believe in God is for those who have that belief to come out of the closest, because the perception that many people do not believe in God reduces prejudice against them, perhaps through a "present company excluded" kind of social logic.