Factual error: The Cunninghams are going to the movies, and Ralph asks Joanie what they are going to see. She says "Psycho" which was made in 1960. The series was set between 1955-1965, this episode would have been set in '57.
Other mistake: June Lockhart is referred to verbally as 'The Honourable Judge McKay', but the end credits say 'Judge MacBride'.
Answer: If all the actors and hands know their roles well enough they could perform the play reasonably well even without a director.
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