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

From: Gregg Vanderheiden <gv@trace.wisc.edu>
Date: Sat, 5 Nov 2005 15:05:46 -0600
To: "'Matt May'" <mcmay@bestkungfu.com>, "'WAI WCAG List'" <w3c-wai-gl@w3.org>
Message-ID: <004401c5e24c$b190b5d0$ee8cfea9@NC6000BAK>

Thanks Matt

Anyone - any others?  


 -- ------------------------------ 
Gregg C Vanderheiden Ph.D. 
Professor - Ind. Engr. & BioMed Engr.
Director - Trace R & D Center 
University of Wisconsin-Madison 

-----Original Message-----
From: w3c-wai-gl-request@w3.org [mailto:w3c-wai-gl-request@w3.org] On Behalf
Of Matt May
Sent: Friday, November 04, 2005 7:49 PM
Subject: Re: Summary of arguements FOR validity -- and another against --
and a third of alternatives

So as not to introduce bias, I will only attempt to answer the arguments
against validity at Level 1.

On Nov 4, 2005, at 1:59 PM, Gregg Vanderheiden wrote:
2) Now I need someone (else?) to send one of the arguments against.


HTML validity cannot be established as a necessary minimum requirement for

Many validity failures have no direct bearing on accessibility, or even any
bearing whatsoever.

In some documented cases, attempting to hack invalid code so that it passes
validation causes the code to be less accessible to AT.

The state of the Web:

Certain functions intended to increase direct accessibility with AT,
including code designed by AT vendors themselves, are invalid, and there are
no signs their use will recede in the foreseeable future.

The percentage of authoring tools (including content management
systems) in today's market that reliably produce valid output at all times
is well under half, and as older products are factored in, the figure
approaches zero.

The production of valid HTML is not a common skill set among everyday
developers, outside of a small group of skilled practicioners.

Validity is not a state commonly understood by non-technical producers of
HTML, who number in the tens of millions.

It may never be possible to make some content valid, because the flaw is
created by a tool or process that cannot be changed by the responsible


WAI and the WCAG WG produce recommendations for increasing accessibility to
PWDs and are not, and must not be seen as, crusaders for or enforcers of
other W3C specifications.

A minimum requirement of validity would consign a large proportion of
accessibility repair work to tasks that may not, in the end, actually
improve things for users.

A minimum requirement of validity would introduce a potentially enormous
amount of time and expense to repair larger legacy sites, for an benefit
that is hard to quantify, and therefore hard to justify.

Establishing a process for producing and maintaining valid content is a more
effective tactic for increasing overall Web validity than specifying that
the final outcome must be valid.

Received on Saturday, 5 November 2005 21:05:48 UTC

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