White sculpted his “bosom” option for Scene 114. “There’s a thing that happens when actors vamp, which is that they repeat themselves,” he said. “So if I can pull out the repetitions, I can strengthen the performance.” He toggled between takes appraisingly. Certain ones Feig had marked with a “VG,” for “very good.” Others were unusable: Serafinowicz cracked up; McCarthy’s head was turned the wrong way. White liked a particular take except for the way that McCarthy said “stop talking” twice in response to Aldo’s “compulsion” apology, so he simply deleted the phrase’s second appearance, cutting to a reaction shot from Serafinowicz to hide the excision. Things still felt slow, so White tried several configurations of the dialogue, snipping and rearranging words like a manuscript editor with a red pen, then finally scrapped the second half of Aldo’s apology outright, along with the first half of McCarthy’s reply. Now the characters talked, amusingly, right past each other:

ALDO: “It’s a compulsion!”

SUSAN (disgustedly): “You know what, I’m not going down like this. Just untie me!”

ALDO: “Bosom — what?”

“See how I pulled those together?” White said happily. “Compulsion to bosom, that’s the connector.” Working microscopically, he’d transformed a tossed-off ad-lib into a solid, streamlined laugh. He leaned back and let the exchange play through again: Boom-boom-boom.

White is a Mormon from Orem, Utah, “down the canyon from Sundance,” he says. As an undergraduate at Brigham Young University, he had screenwriting ambitions, with tastes that leaned toward dramatic material; he acknowledges that his faith squares improbably with his career in raunchy comedies. “I’m the one who went off to join the circus,” White says. As a Mormon, “you’re not supposed to see R-rated movies. And when I was at B.Y.U., it was constantly talked about: How do you make movies in this faith?” When White was cutting “The 40-Year-Old Virgin” — a film he interprets as being “about family values: monogamy, chastity” — he amended the title for his kids’ benefit. “I told them it was called ‘The 40-Year-Old,’ ” he says.

When White was 24, he got a job at Sundance Institute, a production-side sibling of the film festival, where he helped cut workshopped scenes from potential indie dramas. While there, he applied to Columbia as a screenwriting student; the school initially rejected him, then wait-listed him, then finally accepted him. White says that his background in drama helps him to home in on the emotional reality of the scenes he cuts today, even if those scenes include preposterous lines about bosoms and colons: “The early things I did were really serious and dire, and what was great about that was that it was always about the reality of the situation. That’s one of the things I bring to the table — the idea that the joke only lives if it lives in a real environment, a real situation.”

One of White’s mentors at Sundance was Dede Allen, who cut “Dog Day Afternoon” and “Bonnie and Clyde.” Allen instilled in White an unfussy approach. “You run into editors who say, ‘I can’t make that cut, the glass of water is in the wrong place in that take,’ ” White said. “But I’ll say: ‘Who cares? The performance is strongest in that cut!’ Why would you match the glass and take on that worse performance? ‘Matching is for sissies’ — that’s one of the things Dede would say all the time.” White argues that as audience members, we “look at actors’ eyes most of the time, so as long as they’re engaging, you’re going to be connected to that person, and whatever happens elsewhere in the frame is less important.” Increasingly, White is able to have his cake and eat it too, paying digital-effects houses to swap out an unwanted portion of a frame with one more desirable, say, or superimposing an actor’s head at the bottom to fabricate visual continuity between shots.

An opportunity to work with Allen, cutting Robert Redford’s “The Milagro Beanfield War” (1988), arose at the same time that White was mulling Columbia’s acceptance letter. He consulted the dean, who told White that experience on a Hollywood movie was too valuable to pass up. “So I took the job,” White says. He stayed in Hollywood, working his way up the ranks, occasionally returning to Sundance. In 1999, he saw a tape of the “Freaks and Geeks” pilot. White put the word out; an editing slot on the series came open, and Feig hired him. After NBC canceled that show, White followed Apatow, its producer, to the pilot for a never-to-air Fox sitcom called “North Hollywood,” starring Jason Segel, Amy Poehler and Kevin Hart. “It was supposed to be 20 minutes long,” White recalls, “and Judd shot, like, 90 hours of material. I worked really hard trying to get it down to time, and the 45-minute version was funny and smart, but Fox needed it in that half-hour window. We cut it to time, and it just didn’t work.”