Huh. I feel exactly the opposite. I have often said mustard overpowers anything it touches. I grew up in the south though,  where mayo is a food group. A touch of mayo to give a sandwich  a little love,  IMO. Oh and deviled eggs! You can't devil eggs without mayo!  Get the good kind,  with no added sugar,  like Duke's. Or,  make your own. Also,  what do you put in your chicken salad if not mayo?