Where the idea falls flat.
The reason this film could never be a success is because the entire sketch it is based on revolves around one joke. If you never found the idea of trying to determine the sex of Pat funny (And if you match 99% of the American population, you didn't), then you wouldn't enjoy the same joke being repeated over and over for an hour and a half. The joke didn't work in a 2 minute sketch, why make a whole film?
"Mein Fuhrer, I Can Walk" -- Dr. Strangelove