RDDL and XSLT

I've been wondering about how one could define a standard set of transformation rules for a XML vocabulary, and thought RDDL might be the solution but the specification is not very informative. In terms of an application accessing a XML file in some proprietary format, the question is how can an application determine how we can transform this file into a format that can be presented to the user e.g. XHTML. RDDL could allow that information to be accessible from the namespace URI. I envisage this form of usage:

<rddl:resource  xlink:role="http://www.w3.org/1999/XSL/Transform"
        xlink:arcrole="... namespace URI of XSLT output eg XHTML ..."
        xlink:href=" ... " />

 This could be a standard way for authors and applications alike to locate required XSLT resources. Comments?

Lyndon