George Washington Zapped Here (2) - S8-E22
Revealing mistake: When Samantha is showing Martha the washing machine, look at Martha's shadow; it's visible on the "trees" outside the window in the door, making it obvious it is a painted backdrop. (00:05:35)
Answer: Larry had been telling Darrin what it means psychologically that Samantha gave the coat away. Larry said giving it away meant she's happy being married but if she liked the coat it means she desires to be single and carefree. So when Darrin sees the coat, he immediately thinks Samantha doesn't want to be married and the fact that she twitched it means (in his mind) she wants to be a single, carefree witch again.
Bishop73