Other mistake: The background action in the opening credits is slightly unsynchronized. This is most obvious at the "Goodbye gray sky, hello blue" line in the theme song, as Potsie mouths the lyrics. It's also obvious at the "My cycle hums" line, as the girl in the blue plaid skirt shows up at "cycle", rather than "my." (01:13:10)
Other mistake: June Lockhart is referred to verbally as 'The Honourable Judge McKay', but the end credits say 'Judge MacBride'.
Other mistake: The outside of the house does not match the interior setting at all.
Answer: If all the actors and hands know their roles well enough they could perform the play reasonably well even without a director.
BaconIsMyBFF