XSL Transform

An XSL stylesheet is a well-formed XML document. Is there
a reason for it being stringified in an XSLT element?

   <element name='Transform'> 
       ...
         <element name='XSLT' type='string'/>

Would not a more useful expression be:

         <element ref='xsl:stylesheet' minOccurs='1' maxOccurs='1'>

Or however one expresses that as a schema. Or just put it
as an ANY element so the external schema/DTD is not required.

I looked in the archives and could not easily discover an
explanation for the current expression.

merlin