Humor has historically been tied to the mores of the day. The Yellow Kid was predicated on what people thought was funny about the immigrant Irish. When you're different in a society, you're funny.
I still like to keep tapes of the few minutes before the final take, things that happen before the session. Maybe it's superstitious, but I believe if I had done things differently - if I had walked around the studio or gone out - it wouldn't have turned out that way.

