04/21/2004 at 01:00 AM EDT
Talk about being in a class of one's own, David Letterman doesn't really joke about everything. On Wednesday, before Al Gore's politics and media students at the Columbia University Graduate School of Journalism in New York, the "Late Show" host, 53, fielded questions that included why Dave never cracked wise in his monologues about Darryl Strawberry or O.J. Simpson -- unlike, say, another late-night show host, it might be noted. In the case of the former Yankee slugger, Letterman explained, as quoted by The New York Times, "If he shows up dead next to the I-95, we're gonna feel stupid." As for the former gridiron great, "At the core of this was a double homicide, a grisly double homicide." As for appearing in such a distinguished setting (in the interest of full disclosure, the editor of the PEOPLE.com Daily also teaches at the Columbia Journalism School), Letterman said, "When we were coming up here I said to friends, 'I'm very nervous about this.' They said, 'Don't worry, Al will do all the talking anyway.' I'm glad to see that's worked out."