To add to Stuart’s list:
It was helpful when all talkphysics messages were labelled [TP] because ‘TP’ is a rare combination of letters. That made it easy to search one’s emails. (Ditto ‘PTNC’.)
Another thing: If you post on PTNC, the email comes through almost immediately. On TP, it can take several minutes or more. More than once I have posted a comment only to find that someone else has done similarly but it hasn’t appeared on the system.