One more thought about requiring the alt to add to the pile

The spec[1] currently states:
"In some cases, the image is a critical part of the content. .... In a rare
subset of these cases, there might be no alternative text available. "

Given that it is only in  very rare cases (a "rare subset" of "some
cases") where it is considered legitimate in the spec to leave out the alt
attribute.
And these "rare subset" of cases are a clearly defined class of site "a
photo upload site".  Would it not be better to require/encourage the
relatively small number of AT vendors to provide a feature that exposes
images with alt="" (in case the photo site CMS has been designed ot add
alt="" automatically), that a user can enable when he/she visits these
sites?.



[1]http://www.w3.org/html/wg/html5/#the-img
-- 
with regards

Steve Faulkner
Technical Director - TPG Europe
Director - Web Accessibility Tools Consortium

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