... I would include a sentence or two about the risks of using dcc when really sending a bcc (as opposed to a cc to myself).
Perhaps something like
Note that the users listed in the dcc field receive no explicit indication that others who received the message are not aware that a copy was sent to them. This can cause blind recipients to inadvertently reply to all of the sighted recipients of the original message, revealing that they received a blind copy. On the other hand, a normal reply to a message sent via a bcc field will generate a reply only to the sender of the original message, it takes extra effort in most mailers to reply to the included message, and so would usually only be done deliberately, rather than by accident.
Or perhaps an abbreviated version of that...
Hmmm... we wouldn't want to actually *explain* anything in a manpage, would we? ;-) Seriously, that extra info looks good to me. We might be able to do without the last sentence, though; I think people will figure it out pretty quickly.
Jerry -- Jerry Peek, [EMAIL PROTECTED], http://www.jpeek.com/