> If I have a large DTD (say 100KB), and a large XML file (say 2MB);
> what would be the best way to present it over the Web?

Pending implementation of the XML fragment transfer draft, I'd say
that the best way is to transform your document into several smaller
documents.  Ideally, you'd have one master file that makes entity
references to sub-files, and browsers would defer loading of those
component files ( la image loading), but I don't think any of the
existing XML implementations do that.

> Is there a way to reference the ENTITIES (i.e. ISOlat1, ISOnum,
> etc), without requiring the rest of the DTD, for the sake of speed?
> Kind of a pseudo-valid XML document, but more along the lines of
> just being well-formed????

There are two ways to do that.  One way is to actually insert the
relevant entity declarations into the internal subset of your post-
transformation small documents.  This could result in large internal
subsets, but it's possible to scan each mini-document and see which
entities are actually used.  It's cumbersome, but it guarantees that
the recipient will have the necessary declarations.

The other way is to move the references to the entity sets into the
internal subset.  That means that a parser that processes the internal
subset only will see the references to the sets.  However, there's no
requirement that the parser actually retrieve those external DTD
entities, so you're taking a bit of a chance.

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