Letterman's relationship with the soon-to-be-former Hills star has long see-sawed between extremes, starting off intensely fascinated, then a little mean — and now both, in one show. It's as though the late-night doyen knows he should be as mean and cutting with Conrad as he is with other starlets, but finds himself too smitten to muster lasting enthusiasm for such hostility.
In the clip up top, Letterman cuts into Conrad through the simple technique of question-and-answer — the sort of work that leaves plausible (to, say, a publicist) the claim that the host was never intentionally hostile.
Then, because he gets awkward when he has a minor crush, Letterman shows a little too much enthusiasm for the actress in the clip below, restoring essential balance to Late Show celebrity flackery and bringing full circle his reality check of a "reality television" star.
It's almost enough to make you wish Conrad wasn't taking a long, long vacation from Letterman's couch. Things were just getting fun.