dired-do-copy not really cp -p

[Dan Jacobson]

Gentlemen, I accuse the "[-p]" of  dired-do-copy's prompt,
   Copy [-p] * [4 files] to: /tmp/barf
of being a big fat lie!  Firstly, we all know that the real cp -p preservers
group and ownership.  However dired-do-copy doesn't. Try it as root
today. Secondly,
       dired-do-copy is an interactive compiled Lisp function in `dired-aux'.
       ...This normally preserves the last-modified date when copying.
OK, it only mentions dates.  If this is all it mentions, then in the
prompt don't go blabbing about -p unless you plan to really deliver the 
vegetables.