You are correctly stating that a scheme which attempts to avoid MIME
doesn't work well with a MIME message. While I don't think that this
is backwards from what I'm saying, I'm certainly not in disagreeemt
with you as to whether my proposal -- to avoid MIME when it is not
needed -- addresses the case where MIME is needed.
The entire reason for doing the security multiparts work in the first place was
to define a security service that works well with MIME. You now say your
solution is intentionally designed so that it does not meet this primary goal.
So why are we even having this conversation?
If you want to ask the IETF to standardize some scheme for securing exclusively
non-MIME messages, that's of course your perogative, and if you are serious
about doing this you should be talking with the Security Area Director of the
IESG (Jeff Schiller) about forming a working group to do it. But such an effort
has nothing to do with the work at hand, and as such is not an appropriate
topic to discuss here.
Ned