Sometimes it’s useful to maintain a read-only category accessible to one or more groups to follow announcements or mirror a diffusion list.
Problem
Since admins can post anywhere, it can happen that an admin will reply or post a topic in such a read-only category unknowingly, resulting in lost discussion or unnoticed intervention, or even in unsolicited email back to the original mailing-list.
Resolution
When an admin tries to reply to an existing topic, or tries to create a new topic in a read-only category, they should receive a big fat warning greying out the composer and asking them to confirm that they indeed want to do this, suggesting they could quote the topic in another, more appropriate space.