That's a good one - it reminds me of Ms. Manners years ago -
   someone was fired up about a co-workers bad manners and "she was
   gonna let her know" - and Ms Manners let HER know, in no
   uncertain terms, that It is the worst of bad manners to point
   out the bad manners in someone else. And she said it without
   telling her she had bad manners herself. "