Concern with prose in @aria-errormessage

http://rawgit.com/w3c/aria/master/aria/aria.html#aria-errormessage

I'm concerned this line in @aria-errormessage is going to result in duplicated announcements. Reconciling these two different types of user-facing announcements would be very challenging from an implementation perspective.

> Authors may use live regions for the error message element <http://rawgit.com/w3c/aria/master/aria/aria.html#dfn-element> applying either an aria-live <http://rawgit.com/w3c/aria/master/aria/aria.html#aria-live> property or using one of the live region roles <http://rawgit.com/w3c/aria/master/aria/aria.html#live_region_roles>, for example, alert <http://rawgit.com/w3c/aria/master/aria/aria.html#alert>. 

Please change it to recommend one or the other (either @aria-errormessage or live regions) but not both simultaneously.

Thanks,
James Craig