XML Extensibility and versioning

XML.com published an article from Dare Obasanjo [1] yesterday, about XML
Extensibility and Versioning; I've only skimmed through it, but it seems
to touch on several of the points that SpecGL tries to address in
extension and deprecation applied to the specific case of XML languages.

It would be great if someone had the time to look further on whether
some of the points in the article should inspire new good practices or
techniques in SpecGL; I may end up doing it next week, but would love to
see contributions from others :)

Dom

1. http://www.xml.com/pub/a/2004/07/21/design.html
-- 
Dominique Hazaël-Massieux - http://www.w3.org/People/Dom/
W3C/ERCIM
mailto:dom@w3.org