SV: [ubl] Discussion of substitution groups

>The extensible bit is in the vocabulary and how customizers use that
>vocabulary and our normative schema.  Not in how we create our normative
>schema. 

The extensible bit is only in a vocabulary if that vocabulary is extensible.
It seems to me that you're arguing not so much for extensibility but
reusability.

That said, as I've argued before, substitution groups are not as extensible
a mechanism as use of xsd:any.



Cheers
Bryan Rasmussen.