Handling of flagged PM

The current behaviour of flagged private messages seems a bit counter-intuitive:

  1. all moderators seem to receive a notification about it but to some it was unclear why they received it.
  2. replying to flagged PM causes the responder to become a participant in the discussion. Which is surprising because:
    a. it's a private message so third parties getting involved is not what one would expect.
    b. both the one that flagged the thread as well as the potential offender see the other replies from moderators trying to weight in.
    c. two moderators replied and they both assumed they replied to the one that flagged the message.

While 1) can potentially be solved through some rephrasing (subject prefix or email body), I find the behaviour of 2. problematic.

Maybe I've got used to other forum software but can somebody shine some light into the current workflow of dealing with (flagged) PMs ?

Sorry for the delay. It was the first check-box ("it's inappropriate").