The ultimate spoof!
Spoofs, when good, are among my favorite movies. Some of my favorites are Dr. Strangelove, Best in Show, Spinal Tap, Airplane, Groove Tube, and some others. But I have to admit this one is my top choice.
The topic Reiner chose had to be one of the hardest ones to make a good spoof of, but it succeeded, IMO. I've watched this with people who didn't get most of the humor and I even felt a bit guilty laughing so hard as they said "What's so funny?" My response was, "you either get it or you don't." None of the humor could be explained in this or any of the other ones.