Teaching Composition with XML

I’m thinking about ways to use XML metaphorically to teach rhetorical or linguistic concepts. The rough idea goes a little something like this:

XML can be described as a semiotic system in the structuralist sense, with an arbitrary relationship between signifier (element tag) and signified (element content). The arbitrariness of it all puts successful communication at risk, hence schemas (or, if you are old school, DTDs), which establish grammars and vocabularies used to govern communication (data exchange). XSLT, depending on its use, can enact either translation (a transform from one document structure — valid or invalid — to a new one validated against a pertinent shared schema) or rhetorical craft (a transform from one valid structure to another for the sake of presentation).

Please note that I haven’t figured out if attributes work in this little setup.