I don't find a specification for Mutt's threading algorithm in the docs I have, manual and faq. Maybe it's a moving target, but I bet it's pretty stable at this point. As I understand it, Mutt uses In-Reply-To as its highest precedence, which makes sense, but I'm left with the following:
What's the form of an In-Reply-To header? What's the form of a References header? I often need to hack these headers to organize threads where correspondents are careless about replying, but their content is important enough to keep their mail; I'd like to know what spec I should be working to as I hack. Obviously, I can get a good idea of these headers by simply looking at some of them, but a real spec is nicer. Is there a function in Mutt to "force all tagged msgs into a thread (or subthread)" or somesuch? I suppose such a function would add a reference, pointing to the earliest-dated mail in the group, to each of the other mails, but maybe there's a problem with that simple-minded approach. Sometimes I want to send mail to a list that should be threaded under some topic, but it's not really in reply to any particular piece of mail. It seems I want to send with a References header, but not In-Reply-To, with my own unique Subject line that will start a sub-thread. Is there a way to tell Mutt to reference a piece of mail without replying to it? I can always edit the header later after the list sends me back my own mail, but it'd be nicer to do it at the outset. I realize this is really a picky distinction, that an In-Reply-To line isn't the end of the world, but still... TIA, Jim
