Could he really be that miserable?
"I don't consciously try to make people squirm," says David, who's created one of TV's most memorably unlikable characters.
"I'm never aware of making people uncomfortable, honest-to-God," David says. "I had no idea that I could possibly have that effect on people."
The people who work most closely with him — Cheryl Hines, who plays his wife, Jeff Garlin, who plays his agent, and Shelley Berman, who plays his father — swear that life on the set is nowhere near as uncomfortable as David portrays it in the show.
"I've seen a lot of comedians who, when the camera isn't rolling, sit in the corner and sulk," says Hines. "But Larry is not that person.
"We sit around and talk and have a great time," she says.
"Larry is a bit of a perfectionist and puts a lot of pressure on himself," she says. "Now that the show's been airing and has been critically acclaimed, he does feel a great pressure to keep doing outstanding shows.
"Even now in the fifth season, Larry isn't much happier with the takes than he was in the first season."
"Larry isn't morose," says Garlin, "but he's not creating comedic havoc off-screen, either."
While he was writing "Seinfeld," David had two strict rules: no hugging, no learning. At least one of those rules is still in effect.
"For the most part, 95 percent of the show is the same as it was on Day One," says Garlin.
"A lot of time Larry will see how a scene is evolving and sees the changes he has to make," he says.
"It's not like he's a stickler, but he'll adapt to what's happening and to the strengths or weaknesses of the guest actors.
"He's not a jokester — I'm the jokester — but he's a great audience," says Garlin.
"I guess I'm just trying to get all the juice out of the scene," says David.
"There are outlines Larry has written, but we improvise all the dialogue," says Berman, the veteran stand-up comedian who's been discovered by a new audience in his "Curb" role.
"You never finish a scene where Larry doesn't come up to you and say, 'That's great' and pat you on the back."
"Our technique hasn't changed at all — Larry still writes the story outline and we improvise all the dialogue, but it's sort of evolved a bit more," says Hines.
"Once in a while there's a phrase Larry wants us to say because it's important. You'd think we have it down to a science but we don't.'
"It could take two takes or 14 takes, depending on what Larry's happy with."
The Larry David featured in "Curb" — which returns after an 18-month hiatus at 10 p.m. Sunday on HBO — is a skewed ver sion of the real David, who co-created "Seinfeld," wrote most of its classic episodes and made tens of millions off the show.
But it's not that far off the mark.
"People make me uncomfortable," David says. "Most social experiences are, to me, fraught with discomfort. Why is that? I don't know.
"I think it's all the things [I'm] thinking and not saying," he says.
"He is the hope for today's comedy and for new comedy," says Berman. "I refer to him in the best of ways as a 'retro comedian.' He is everyman and makes people nervous because he is everyman.
"He's the schmuck in all of us."