I think this is one of the great moments in P2 that really illustrates what you were saying about Elizabeth and Mrs. Clay. When they're sitting waiting for Lady D's carriage and Elizabeth is going on about the wonderful marzipan. She instructs Penelope to agree with her - which she does. But the next moment she has the opportunity to put the candy down again without eating it and she does with such alactrity that you just know she hates marzipan! It's not in the book, but it illustrates her life with them.