I would suggest that you have shown the need for a new type of
Let's do that as a registered disposition type once the basic
content-disposition is out of the door.
BTW: will you suggest the use of the ietf-types(_at_)uninett(_dot_)no list for
the discussion of new content-dispositions, as is now done for
content-types? (It ended up @uninett.no after a long and confusing
journey from RFC 1590. Send to ietf-types-request(_at_)uninett(_dot_)no to join)