Mary Tyler Moore has quit Neil Simon’s new play while still in rehearsals. “Ms. Moore was seen storming out the backstage door minutes before the 2 p.m. curtain on Wednesday. Several sources close to the production said she had just received a brusque letter written by Mr. Simon and delivered by his wife, the actress Elaine Joyce, reproaching her for not knowing her lines. Ms. Moore had received prompting through a microphone in her ear, the sources said.”