In the post-chapter chat I mention reaction shots.
Here’s the PERFECT EXAMPLE (esp at 1:00, 1:26, 2:20, 2:45, 2:57, 3:13)
And, notably, when we saw The Producers on Broadway, we went with someone who had never seen the movie. Without those reaction shots (that is, with the song just being done as The Song) she was both horrified and offended (and not Jewish) until we explained to her that it was SUPPOSED to be in seriously bad taste.
She wasn’t impressed.
Lesson: Reaction Shots Can Make or Break You.