I mean, it is surprising and it isn’t. As I said when I first saw that article, it definitely bucks convention to think that Yale would be behind the trend on something sociosexual, and that Princeton would have gotten there first. But there are totally ways to rationalize this, and it’s especially easy to make the point that Princeton is not institutionally more conservative than Yale (undergraduate student culture is a different matter).
Princeton and Yale began coeducation in the same year. Princeton followed Yale by only three years in establishing a gay student organization (still both in the heyday of the gay liberation period). Yale has never had a woman president. It was five years behind Princeton in establishing an administration-run LGBT resource center. The institutional support for these types of reforms linked to a more developed understanding of gender and sexuality and a larger acknowledgment of the heterosocial real world in which we live has developed at relatively the same pace at both institutions.
As I think the YDN article indicated, what distinguishes Yale here is a logistical challenge provided by its all-encompassing residential college system. This is certainly a common hurdle: Harvard, which also has a developed residential college system, has a very limited GNH policy. Princeton, whose residential colleges serve only freshmen and sophomores, had little difficulty in extending GNH to upperclass students, but I can tell you from firsthand knowledge that giving underclass students the option (because of the residential colleges) is going to be a nearly insurmountable hurdle.
I’ve been thinking about this all day, and it’s starting to make more and more sense why things have panned out the way they have. Princeton’s eating clubs have entrenched a certain type of conservatism on campus, but it’s certainly not one reflected in the administration–our president is one of the most progressive of any university. And I’m not precisely sure how Yale got the “gay Ivy” designation (though George Chauncey has some ideas) but I’m very dubious about the extent to which that’s supported in fact.