RE: Schism in the Semantic Web community.

Alan,

You quote:
> 
> 2.1 Document Conformance
> Several syntaxes have been defined for OWL 2 ontology documents, some
> or all of which could be used by OWL 2 tools for exchanging documents.
> However, conformant OWL 2 tools that take ontology documents as
> input(s) must accept ontology documents using the RDF/XML
> serialization [OWL 2 Mapping to RDF Graphs], and conformant OWL 2
> tools that publish ontology documents must, if possible, be able to
> publish them in the RDF/XML serialization if asked to do so (e.g., via
> HTTP content negotiation). OWL 2 tools may also accept and/or publish
> ontology documents using other serializations, for example the XML
> Serialization [OWL 2 XML Syntax].

Which says qualifies the "must" in "MUST, if possible, be able to ..."

When is it not possible?  (follow-up Q if relevant: who decides?)

	Andy