Sorry, but this cannot be totally correct. I failed to articulate this well on the call.
If the arbitrary use of AT can be assumed to satisfy SC, then 1.4.3 Contrast (Minimum) (and 1.4.6 Contrast (enhanced)) is trivially always satisfied because of AT products like ZoomText and MAGic (since they can be used to increase contrast).
I am going to through the SC and see if I spot others that are essentially nullified if the use of AT can be arbitrarily assumed.
________________________________
From: Gregg Vanderheiden [gv@trace.wisc.edu]
Sent: Thursday, June 21, 2012 6:09 PM
To: Peter Korn
Cc: Hoffman, Allen; Andrew Kirkpatrick; David MacDonald; public-wcag2ict-tf@w3.org
Subject: Re: Interaction Context
The WCAG WG just passed the following resolution
RESOLUTION: add the note... NOTE: With the exception of one success criterion (1.4.4 - that specifically mentions that the effect specified by the success criterion must be achieved without relying on an assistive technology) authors can meet the success criteria with content that assumes use of an assistive technology (or access features in use agents) by the user, where such assistive technologies (or access features in user agents) exist and are available to the user.
Gregg
--------------------------------------------------------
Gregg Vanderheiden Ph.D.
Director Trace R&D Center
Professor Industrial & Systems Engineering
and Biomedical Engineering
University of Wisconsin-Madison
Co-Director, Raising the Floor - International
and the Global Public Inclusive Infrastructure Project
http://Raisingthefloor.org --- http://GPII.net