H. L. Mencken? Jack Dempsey? Peg Bracken? Bennett Cerf? Alexander Woollcott? Stewart Holbrook? William Safire? Apocryphal? Dear Quote Investigator: Forceful newspaper columnists often receive opinionated and hostile responses. There is a powerful temptation to send a sharp retort. Yet, one famous journalist typically replied with a brief disarming note: Dear Sir (or Madam ), You …