> David is proposing that we use two result-document elements 
No. Just one, there is no need to serialise the validated  tree to a
result document if you do not need it.

> Is this the way we are supposed to work in XSLT?
personally I've not used a schema aware processor, and if I did I would,
as I said, just modify the local copy of the schema against which I was
validating, but I offered it as a suggestion.

David