Deliberate mistake: Whenever a punch is thrown in this series, the punch either stops before it hits the person or goes beside them. It's most obvious in the last episode when General Melchett says 'Excellent native cockney wit' and punches Baldrick.
Deliberate mistake: Around the 26 minute mark, when Charles Brandon joins Margaret for a game of cards during their voyage to Portugal, Margaret has a glass of wine (and later Brandon) in which the liquid is not sloshing around As It Should Be on a ship that is rocking and swaying the way it should. (00:26:10)