what you seem to be wanting is for IETF to bless nonstandard practices
for a widely-used, critical service that is sensitive to disruption -
or at least, for IETF to make such practices appear "equal" to standards.
I think that would counterproductive to IETF's purpose.
We don't want the IETF to "bless" nonstandard practices. We just want
a useful registry that helps people in implementation and prevents
standardization of fields that have already been used for a different
meaning.
all of this sounds fine to me. I just don't want the registry to
serve as a means to circumvent the standards process or to allocate
header field names that should be reserved for standards.
Keith