On Mon, 11 Jan 1999, Jiro Maeda wrote:

I know that some of you enjoy giving out public C&C but I feel that it
might embarrass the author if his fic were dissected in public, with
everyone noting out it's flaws.  Some people even do this tactlessly,
adding insult to injury.  Treat the new authors a little gently or if you
can't, just say it to their faces, and not in front of several other list

The FAQ is quite clear on this point. Authors who don't want their fics
"dissected" on the list have the option of asking for private responses
only in their author's notes. If they don't do this, then public comments
of any type (as long as they're not things that are otherwise
forbidden, like personal flames against the author) are fair game. While
being frequently tactless probably won't win you many friends, it's not a
violation of list policy.

-Tybalt