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Re: Summary of arguements FOR validity -- and another against -- and a third of alternatives

From: Carlos A Velasco <Carlos.Velasco@fit.fraunhofer.de>
Date: Sun, 06 Nov 2005 15:25:13 +0100
Message-ID: <436E1249.8000006@fit.fraunhofer.de>
To: Gregg Vanderheiden <gv@trace.wisc.edu>
Cc: w3c-wai-gl@w3.org

Hi Gregg, all,

Not being a good-standing member, I cannot help to jump in the 
discussion and throw my 2 cents (of €). Following Gregg's advice of 
front-loading information, here is a summary of this post:

*IMHO, Validity is essential for accessibility, and thus shall be P1*

I will try not to repeat the arguments of Gez, Roberto and others 
supporting this position. However, there are some points that worry me 
from the non-validity position in this group (no offense meant, please):

- It seems to me that accessibility is interpreted in a very narrow 
sense, i.e., if IE+MSAA+JAWS can deal with non-valid content, then, 
there is not any problem for any assistive technology. We do research on 
new AT devices for different user groups (mobility and learning 
impaired, mainly), and invalid content is a huge burden in our work. 
Unfortunately, we dared to use a different rendering engine and API to 
access the DOM, which is not as forgiven with mistakes as the mainstream 
one. And of course, we had to add additional error recovery routines to 
be able to render invalid content to our users. If valid content were 
the rule and not the exception, our work and of many others that develop 
or research AT for the Web will be easier.

- Furthermore, if that interpretation (or "baseline") stands, then I 
believe the vendor-neutrality of W3C is at stake here, because we are 
adapting WCAG 2.0 to a given OS, with a given API and a given AT vendor. 
IMHO, that is a repetition of the famous "Until user agents ...".

- Some people have argued that AT vendors do not have the resources to 
fix their tools and adapt them to become standards compliant. I.e., "if 
Flash is accessible via <embed> to a given screen-reader, and its 
manufacturer does not want to bother to implement <object>, then WCAG 
2.0 shall not include validity." Aren't we punishing vendors that do 
want to conform to W3C standards? Again, where is the vendor neutrality 
here? (Bob, I used Flash as an example; nothing against Macromedia)

- It is argued that actual CMS do not produce always valid content. 
Well, some do and some others don't. I believe I should not give names 
here, but we are aware of a CMS that provides the author with the 
possibility of publishing and testing for valid content with a given DTD 
or schema.

- Retro-fitting of old (and invalid, and inaccessible) content: I will 
not claim I am the most competent in this area, but my group does have 
experience working in retrofitting huge portals (more than 100,000 Web 
resources of different kinds, and growing daily) for the German 
government. Of course, nobody expects the whole content to become 
accessible in one week, not even in one year, but fixing validity errors 
as a first step, reduced accessibility issues for many resources.

- Advocacy, harmonisation and education: if validity is removed, then 
the whole set of techniques documents will become a chaos. For example, in:
<http://www.w3.org/TR/WCAG20-HTML-TECHS/#imagelink>
the example of the image used as link could be as well:
<a href="routes.html">
   <img src="topo.gif" /> <!-- Why to write an empty alt here? It
   wastes bandwidth -->
   Current routes at Boulders Climbing Gym
</a>
After all, validaty is not an accessibility issue ... or is it?

- ATAG 1.0 and ATAG 2.0

ATAG 1.0 had this guideline:
<http://www.w3.org/TR/ATAG10/#gl-language-support>
<blockquote>
Guideline 2. Generate standard markup.

Conformance with standards promotes interoperability and accessibility 
by making it easier to create specialized user agents that address the 
needs of users with disabilities. In particular, many assistive 
technologies used with browsers and multimedia players are only able to 
provide access to Web documents that use valid markup. Therefore, valid 
markup is an essential aspect of authoring tool accessibility.
</blockquote>

Unfortunately, it seems that ATAG 2.0 thinks this issue is a hot potato 
  and delegates this "standards conformance thing" to WCAG 2.0:
<http://www.w3.org/TR/ATAG20/#OtherDocs>

<blockquote>
...
- Authors make use of the accessibility features of different format 
specifications, *use markup appropriately*, write in clear and simple 
language, and organize a Web site consistently. The "Web Content 
Accessibility Guidelines (WCAG)", version 1.0 [WCAG10] or version 2.0 
[WCAG20], explains the responsibilities of authors in meeting the needs 
of users with disabilities.
</blockquote>
(emphasis added).

Sorry for the long posting, but IMHO this is a very important issue.

regards,
carlos
-- 
Dr Carlos A Velasco - http://access.fit.fraunhofer.de/
Fraunhofer-Institut für Angewandte Informationstechnik FIT
   [Fraunhofer Institute for Applied Information Technology (FIT)]
   Barrierefreie Informations- und Kommunikationstechnologie für Alle
   Schloss Birlinghoven, D53757 Sankt Augustin (Germany)
   Tel: +49-2241-142609 Fax: +49-2241-1442609
Received on Sunday, 6 November 2005 14:25:26 GMT

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