Deliberate mistake: In the scene in which Ace is in the asylum, he breaks into a storage closet to view Finkle's belongings that were left behind when he escaped. At first the doorframe is such that the door closes against about an inch of wood, meaning the lock would be behind this wood, so Ace couldn't pry it open. In the closeup, the door's flush against the frame so Ace can use the sign to get between the door and the frame. In the wide shot it's back to how it was. (00:58:55)
Deliberate mistake: In the final stadium scene, the scoreboard sets forth that it is the 2nd quarter, 3rd Down and 6 yards to go. The game clock indicates that 15 minutes are left in the quarter. The announcer indicated that it was the start of the 3rd quarter, and neither team kicked off.
Chosen answer: That scene was cut originally by the director Tom Shadyack because the scene did not support the story and thought it slowed the film down. (And the scene was cut from the US version as well.) It was added back later in TV versions of the film. Fan enjoyed the scene so much they asked it be put back in the film version. I know the DVD has it because I own it. It's hilarious!