Thanks for the link. Interesting that the audience in this video found this all to be quite amusing; however he was talking serious stuff here; So was the laughter because of a misunderstanding because audience and speaker?
So maybe it doesn't quite sound so funny to me because in our age we are used to this kind of reasoning, and them back in the seventies weren't?
But, don't take the speech purely at face value -- Adaptation (the movie) leaves it ambiguous about whether this is wisdom, puffery, or accidentally true for the wrong reasons.
Also, it should be pointed out that Kurt Vonnegut had the kind of childhood that would probably leave anybody numb to the ups and downs of life, and also lived through the firebombing of a German city. Everything in his oeuvre is about how impotent human stories are, to prepare people for 20th-century scale horror. So take that as you will.
The idea of a the significance of the sequential change in mood in a story reminds me of the "qualitative tempo trajectory" that underlies DJ sets (section 3.2):
(Found here: http://austinkleon.com/2005/12/17/graph-a-story-with-mr-vonn...)