In the charming 1988 Best Foreign Film "Cinema Paradiso," set in a small pre-war Italian town, the projectionist has to preview every imported American film for the local priest, who sits and rings a bell at each scene containing a kiss so they can be spliced out before the paying audience arrives. Spoiler: In the heartwarming ending, the young boy who had befriended him comes back to town after the death of the projectionist, to find a gift has been left for him: A reel of film, which he projects for himself, and finds it's all the years of removed Hollywood kisses, spliced together one right after the other.
I remember some years ago reading a reply, from a film critic to a newspaper reader, about a letter he had received from her. He had reviewed Cinema Paradiso in glowing terms, and was then surprised to receive a letter that was incandescent with rage.
The cinemagoer was disgusted by what she had seen, and didn't understand how such an epic display of toilet humour, slapstick violence and general crude behaviour had attracted any sort of positive response, let alone the recommendations he had given.
The critic pointed out that it sounded like she had probably been to see "Guest House Paradiso", a very different movie...
Well, I have no idea. But I attended a taping of a sitcom once, and the way it worked is they had mics hanging above all the parts of the audience. Before they show they had a warm up comic, which both put us in the laughing mood and gave them a chance to record our particular audience laughing really hard.
Then when the show was recorded, we actually did laugh pretty hard. You know how you laugh louder when you're at a comedy show or at a movie theater than when you're home alone watching the same thing? Because of peer pressure? It was like that. You laugh harder in the audience.
And then they would "enhance" the laughing by taking the recording of us from earlier and playing it over the spots where we laughed live, especially if they end up using a second or third take, since were didn't laugh as hard.
Also I remember in our episode there was a joke where as the live audience we could see the payoff right away, but on the TV the camera did a slow pull back to reveal the joke. They added in our recorded laughter for that. I remember because I laughed at home but not in the studio.
So it's sort of a combination. But except in those rare cases they don't really add in laughter where there was none. They just enhance the live audience.
There is a very mesmerizing art piece by Mungo Thomson called American Desert [0]. Where he has taken the road runner cartoon and only left the landscape bits. It is beautiful.
I would like to watch the edit of only deleted scenes strung together.