Keith Moore writes:
The thing to do is to get UA functionality right, _then_ to see what
new protocol frobs (if any) are appropriate.
One of the crucial MUA features is to automatically communicate certain
information to recipients. Communication _requires_ protocol support.
Specifically, in various situations, the recipient needs to know that
followups go to T, and replies go to R, where R isn't contained in T.
The protocol needs to support this communication. But the old de-facto
standard protocol always includes R in T. That's why the protocol had to
be changed.
Of course, I went through all this in detail in the first message in
this ``Understanding response protocols'' thread. You're now officially
going in circles; congratulations.
---D. J. Bernstein, Associate Professor, Department of Mathematics,
Statistics, and Computer Science, University of Illinois at Chicago