DocBook namespace use policy

One of my DocBook TC action items was to state a policy regarding the use of the 
DocBook namespace.  Here is the wording I would suggest.

"The DocBook TC does not prohibit users from adding new elements to the DocBook 
namespace (http://docbook.org/ns/docbook). However, such new elements are not part of 
the DocBook standard unless they are approved by the DocBook Technical Committee."

Do we need to say more?

Bob Stayton
Sagehill Enterprises