I’m looking for information about rationalist houses, but the wiki page on the subject is sparse.

The most salient questions for me are:

• What is their geographical distribution? I know there are plenty in the Bay Area, and I think I have heard that there is only one in NYC.
• How frequently are there openings?

Your example does not seem to depict a mind projection fallacy. You might contend that the Christian doesn't have a basis for his assertion, but he doesn't seem to be confusing the map with the territory.