> Michael,
> 
> Your comment with regards schema awareness and information 
> being used by the XSLT processor, what information is used 
> and where/how?
> 
> Thanks for your help/pointers.
> Luke
> 

You might find this article helpful, though it's not 100% up-to-date:

http://www.stylusstudio.com/schema_aware.html

Michael Kay
Saxonica