> Why does this group seem to feel there is an overpowering need to develop a
> DTD that can be used to validate the compound structure, rather than its
> individual fragments?
I think your model of "compound document" is too simple. You seem
to model it as a set of self-contained fragments enclosed in a
container.
I expect to see much more complex documents: a Chemical ML description
of a molecule, with (a) embedded HTML English-language documentation,
which itself contains several inclusions of MathML, and (b) a SMIL
document that marshals a non-XML movie of the molecule. How would
you validate just the HTML part, given that the HTML DTD does not
understand MathML?
-- John Cowan http://www.ccil.org/~cowan cowan@ccil.org You tollerday donsk? N. You tolkatiff scowegian? Nn. You spigotty anglease? Nnn. You phonio saxo? Nnnn. Clear all so! 'Tis a Jute.... (Finnegans Wake 16.5)