Re: documentation for UA interoperability

| One of the things we haven't yet discussed (or did I miss something?)
| is the interaction between different XML systems and what this might
| necessitate in terms of documentation. Since I've spent a large amount
| of time worrying about reverse-engineering the HTML DTD, this is
| something I'd like to get clear from the beginning in XML. In HTML,
| there is no need for documentation on elements, as long as all UAs
| read and implement the HTML spec. This is not necessarily the case for
| XML, where UAs will need documentation on elements to enable
| interoperability.
| I don't know whether this should be in the XML spec itself, or in
| ancillary documentation covering UA conformance. It seems pretty
| obvious that this has to be documented, but I think it also needs to
| be specified how, and what level of documentation is enough. Note that
| when I say "DTD fragment", I mean "in whatever syntax". If I'm too
| early in bringing this up now, just tell me and I'll repost at a more
| suitable stage.

This is an entirely legitimate concern, but one that probably belongs
to a later stage of the effort.  Maybe in Phase II (December-March) we
can spin this off as a parallel project.