now you're moving from the realm of specifying 'features' or
'default handling' of the object into specifying layered encodings.
and this was something that we were very unwilling to do when
we defined MIME. The feeling was that having an arbitrary
number of cascaded encodings was likely to be detrimental to
interoperability.
I thought this too until I realized these were simply strawman names in
Martin's example. I wish he had used other names since the ones he chose invite
criticism of this sort. OTOH, we've been unable to come up with a good example
of a possible suffix that would be orthogonal to -xml...
In any case, MIME flatly forbids the specification of encodings as content
types, so this is a moot point.
Ned