----- Original Message -----
From: "William Herrin" <bill@herrin.us>
Respectfully, your MUA is not the only MUA. Others work differently.
GMail, for example, follows the message IDs as you say but assumes that if you change the subject line in your reply (more than adding "Re:") then you intend to start a new thread from that point in the discussion. It groups messages accordingly.
This is not an unreasonable expectation: if you merely want to continue the current conversation without going off on a new tangent then there's no need for a different subject line.
Maybe it's not. Looking at threads in NANOGs piper, though, it's easy to see threads where the Subject line evolves to follow the conversation, without dropping people who still want to participate in it. The fact that the "(was: old subject)" convention continues in good service to this day, *even though no mailer does that for you* (so far as I'm aware) suggests that people will put in the effort, to me at least. The number of times when I've consciously wanted to break a reply chain -- and usually was not provided with the facility by my mailer -- is much smaller than the number when I wanted it to continue. The only mailer I remember being able to do it in, really, is mutt, where you could get all the headers into vi, and delete In-Reply-To:. Cheers, -- jra -- Jay R. Ashworth Baylink jra@baylink.com Designer The Things I Think RFC 2100 Ashworth & Associates http://www.bcp38.info 2000 Land Rover DII St Petersburg FL USA BCP38: Ask For It By Name! +1 727 647 1274