It's just [Byron] setting the comics up with generic straight-man lines because they CAN'T talk about anything topical.
It's interesting to see the lengths they've taken to avoid letting the viewer know they're actually watching a 15-year-old show. I've mentioned this before, but they edited out Byron's monologue in the more recent reruns...the ones from about a decade ago still had Paris Hilton and Myspace jokes.
Every so often you might hear a comic talk about something like how great it was that Obama
just got elected, but for the most part it's exactly what you said.
Byron throws the comic a softball and lets them riff for two minutes.
/Although I have seen a few non-deceased comics on the show
//You couldn't be more leashed!