Re: Sub-trees (was Re: False threads)

On Tue, 13 Jul 1999 17:54:33 EDT, Valdis.Kletnieks <at> vt.edu said:
> >   "An MUA SHOULD NOT generate a Reply-To/References header to a message
> >    if the sender has modified the subject of the message."

On further pondering, the correct test is not "has the user modified
the Subject: tag", but rather "has the user included any cited text".

If there's cited text, it's either another entry in a thread or the
start of a new subthread.  If there's no cited text, there's no
context of the thread left, and thus it's not on the thread anymore.

This of course is merely a heuristic, not an algorithm, as
every once in a while, a follow-up is made that doesn't leave any
cited material.  But it's probably close enough for a "SHOULD (NOT)"
requirement.

/Valdis