(click to enlarge...sorry it's blurry)
When I was a teacher, an administrator asked me to run a seventh- and eighth-grade "elective" about humor, and I declined because I felt there would be a conflict of interest: if the elective were to have any value at all—that is, if I were to do it seriously, academically, rather than treating it as a kind of organized waste of time—then some of the positions that I, as a teacher, was required to take (values I was required to uphold, standards I was required to enforce) would become untenable. For example, if one student put another student down in a hilariously witty way, I would be entirely comfortable telling him that it was unacceptable, and in an English class I'd be prepared to pretend that I was not amused, but could I, in the role of humor teacher, say in good faith that it was not witty? Wit is amoral: sometimes things that are ethically questionable are unquestionably funny. Arguably this isn't even merely an occasional unfortunate coincidence but rather inevitable given the nature of humor. The nature of humor deserves more focused attention separately elsewhere, but I bring it up because the use of the word gay where it is roughly synonymous with the word lame* (as above) is, at the very best, juvenile and irresponsible**—and it would be hard to argue that it isn't at least somewhat disrespectful, and it's very possibly hateful, oppressive, and even menacing—but can I really go so far as to say that it simply isn't funny? Like, in any context? Not the least bit amusing, ever?
No, I cannot.
* Of course a problem in itself. Do we even have a word for this concept that isn't somehow offensive? I suppose you could say embarrassing? Or—oh, I've got it: retarded.
** When I would discuss this problem with students, someone would inevitably say, "But I'm not talking about gay people when I say that something is 'so gay'; I just mean that thing is stupid," and I would sometimes reply, "OK, well, how would you feel if I said, 'I'm not talking about black people when I say that something is "so African–American"; I just mean that thing is stupid'?"