The guy who laughs off camera is a friend of mine's dad. He was on the crew that filmed that. The remarkable thing about it was that Bud Haggart didn't have a script for that. He had an abbreviated one and winged it from there.
This was done after filming several genuine ads. The crew stuck around and filmed this one just for laughs. --Bob
Genius so so funny, reminds me of a course I went on where the night before all the guys had a little too much to drink and this is what the lecturer sounded like.