In all seriousness, I shouldn't joke about things like that. Cliff Clavin is just a character that John Ratzenberger used to play, and no more represents the real Ratzenberger than, say, The Underminer does.
(In all seriousness, for real this time, I offended one of my friends on IRC the other day by trying to bring my "Pope KT" bit to IRC. I feel bad about that, but... well, if I can't make Pope jokes, nobody else gets to make furry jokes. So There.)