Ah yeah, speaking relative to other forums, I can see your point. It appals me sometimes how thick some people self-labeling as "atheist" can be.
Rationality and rationalism suffer the "what do you mean by that?" problem, yes. I think LW could do with more understanding that the local usage is quite explicitly LW's (or EY's) understanding of the word. Not that I consider this a big problem - and I expect the world will label the local variety in some unambiguous manner shortly after EY's rationality book comes out. (I think "Yudkowskian rationalism" is a hot favourite for what will become the philosophical term, clunky and guru-identifying as it sounds.)
I think if someone showed up hot on discussing the various philosophies that have been labeled "rationalism", they would get a gentle and polite "that's not how we use the term here" and a pointer to a relevant EY post or two.
(I can picture the stupid bad reviews of EY's book confusing multiple historical understandings of "rationalism" and assuming that's what it's for already. Like the reviews of The God Delusion only worse.)
Well, they are atheist in almost any of the likely or useful senses. And to be fair, a lot of the ones I found irritating were highly intelligent. The problem was a classic one for an awful lot of bright people. They'd been surrounded by people who were fairly blatantly irrational, or at least appeared so to a certain kind of mind that takes the religious claims literally. They'd seen these ideas as wrong, and not understood how anyone could hold them. Then they'd found a group of people who'd rejected the same things and so naturally made very strong emot...
You see, I've seen the word "rationalism" used to mean all five of these things at different times:
Edited to reinstate that proposed solution, since this discussion is presumably finished.