A nice explanation here.
https://playboysfw.kinja.com/late-night-david-foster-wallaces-first-published-fict-1304018034
I bolded the relative takeaway.
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"If he wants to make me look silly, I guess he's welcome to try," I said. "I guess."
Rudy swirled the contents of his own glass. "That's just the attitude I've tried to get her to cultivate," he told ****. His ice made a sound as he crossed his legs and looked at ****'s white cat. He smiled grimly. "She thinks he's really going to be like what she sees."
The two of them smiled, shaking their heads.
"Well, he isn't really like that, of course," **** told me. ****, who is NBC's vice-president in charge of broadcast resources, has maybe the smallest mouth I have ever seen on a human face, though my husband and I have known him for years, and Charmian, and they've been dear friends. His mouth is utterly lipless and its corners are sharp; the mouth seems less a mouth than a gash in his head. "Because no one's like that," he said.
"That's what he sees as his great insight. That's why everything on the show is just there to be ridiculed." He smiled.
"But that's our edge, that we know that, Susan. If you know in advance that you're going to be made to look ridiculous, then you're one step ahead of the game, because then you can make yourself look ridiculous, instead of letting him do it to you."
I cocked an eyebrow. "I'm supposed to go out of my way to look ridiculous?"
My husband lit a cigarette as his old superior stood. "It has to appear that way, yes." Rudy's brand is that foreign sort that lets everyone around know that something is on fire. "It's got to be clear it's your choice," he exhaled. The couch he sat on was in a slant of sunlight. The light, this high, seemed bright and cold; his smoke hung in it like ink in water.
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Everything is there to be ridiculed, including Paul Schaeffer ridiculously jamming with bands he has absolutely no business providing musical accompaniment to. I loved when the La's handed him a tambourine.
**** is known for his tendency to fidget. He will stand and sit and stand. "That's good advice, Rudolph. There are definite dos and don'ts. Don't look like you're trying to be witty or clever. That works with Carson. It doesn't work with Letterman."