Good question. But it should be answered by someone who has been here longer than I.
You are correct that it doesn't refer to rationalism vs empiricism - we tend toward the empiricist side of that debate. It is not really a philosophical position - more of an aspiration.
I've been lurking here a bit, and am trying to understand what people here mean by rationalism. Many articles here seem to refer to discussion participants as rationalist while meaning very seemingly-different things, including intelligent, socially awkward, well-educated, and unencumbered by education. I'm trying to make a little more sense of the word/concept.
Surely it does not refer to rationalist in the empiricism/rationalism divide, because it doesn't seem to be used in quite that way.