Update regarding DR 09-0157

[Rick Jelliffe]

There may be a technical problem with both alternatives.

xsd:all  is only allowed in the top-level of the component declaration 
in XSD 1.0 (i.e., what you have after you have made all the 
substitutions.) So you cannot extend an xs:all, either by groups or by 
derivation-by-extension, as I understand it.*

Solution: spell them out separately and perhaps a comment to note the 
relationship.

Cheers
Rick

For a discussion on this, and proof that no matter how bad IS29500 may 
be, it cannot be worse than W3C XML Schemas, see this discussion!

        http://xsd.stylusstudio.com/2004Jan/post05006.htm