Other mistake: In "Broadway Bro Down," when Shelly and Larry are playing Settlers of Catan, Shelly tells him, "And I got a victory point for the most roads connecting settlements." In the game, there's a two victory point bonus for the longest road, but no points for getting the most roads. (00:14:10)
Plot hole: Mr Mackay says he has been working hard on the tooth decay play for 6 years. When he says why it's so important to him, he says it is because it took his father 2 years ago. The monologue exaggerates the length of time he's spent working on the play by saying it was a long time, and exaggerates how hurt he still is that his father was lost by saying it was quite recent. Perhaps the two numbers were stated the wrong way around. (00:15:35 - 00:16:45)
Answer: He appears in at least 5 other episodes, but usually just as a background character. He can be seen at Cartman's party in "Immaginationland". He was also one of the kids trying out to replace Butters in the "Professor Chaos" episode.
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