comments on draft-hoffman-char-lang-media

In a private conversation about media features and
draft-hoffman-char-lang-media,
I thought that it became clear that we should suggest two clarifications on
the role of a 'language' and 'charset' tag registered in
draft-hoffman-char-lang-media; in particular, a 'language' feature describes
a preference (a client that can accept language=fr might also accept an
image of a sunset that has no language, or a multilingual document, etc.)
but that the 'charset' feature describes not only the ability to process
the particular charset but a stronger requirement, that the data be
delivered
as *labelled* with the named charset. So if you want charset=us-ascii, you
don't want charset=ibm367 (even though they're the same).


I think that we might want to consider revising the feature registration
BCP to encourage registrations to be clearer about whether a feature
represents a preference, capability, characteristic, and whether the
feature requires explicit labelling as such.

Larry