There are certain types of humor, Rinslinger, that work precisely because one already knows the punch line. The show "Laugh-In" was largely based on that principle, for instance. It's one's anticipation of the approaching punchline that provides the humor.

One comedy that never loses its power for me is Groundhog Day. It's a very funny and very wise movie which makes a great point about karma and human existence. It could be seen as a parable about reincarnation and the search for wisdom on the part of the human soul, matter of fact.