Abstract Roles and usage

I know that there is a separate discussion going on about how abstract
roles are presented in the ARIA 1.1 Core document.  However, independent of
that, I would like to request that the text about them be changed.  It
current reads:

NOTE

window is an abstract role used for the ontology. Authors should not use
this role in content.

I think this should read "Authors MUST NOT use this role in content."

-- 
Shane McCarron
Managing Director, Applied Testing and Technology, Inc.