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RE: Validation as test for basic accessibility

From: Bailey, Bruce <Bruce.Bailey@ed.gov>
Date: Thu, 10 Nov 2005 09:13:46 -0500
Message-ID: <CCDBDCBFA650F74AA88830D4BACDBAB50B2D49B4@wdcrobe2m02.ed.gov>
To: <w3c-wai-gl@w3.org>
Cc: "Maurizio Boscarol" <maurizio@usabile.it>

>> The actual hypothesis is something like:  
>> "Paying attention to *only* validity results in highly 
>> accessible web sites."  

> Who decided this is the actual hypothesis?  It's not mine.

It is offered as a compelling reason why validity should be Level 1 success criteria.  The hypothesis has not been rigorously tested, but it *is* supported by experiential evidence and therefore should not be dismissed.

> I've already stated my hypothesis:
> "Validity is a preliminary, necessary requirement to accessibility"

I agree with your hypothesis.  It is the essence of why validity is a Level 1 SC.  But it is true because the end goal of accessibility is not a binary condition (like validity), but the result of a process.  Sure, it is possible to pay attention to accessibility without notice to validity, but that route is a great deal much more work.  Part of the reason to elevate validity from its status in WAG 1 is to enable people who care about accessibility to better recognize its importance.  They are missing that now.  The evidence of the past five years is that institutions have *not* been able to figure this out for themselves.  The WAG has this opportunity to help them.

> We need to try to falsificate it. If we can't, we can hold the 
> hypothesis. If we can falsify the hypothesis, then we can't accept it.

We are not solving a mathematical logic equation.

No one has objected to Yvette's observation that validity is necessary but not sufficient. 

The proper vehicle for WAY to address "necessity" is in WCAG.

Validity as a P2 in WCAG1 has not proven to be enough.

> As a process, validation is extremely useful.

It is stronger than that.  It is necessary in order to have accessibility be more than an expensive last-minute add-on.

> If we aren't able to distinguish "product standard" and "process 
> standard", we're not walking a long way.

I do agree with you that validity, as an end-point test, probably has more ramification for process improvement than some other Level 1 SC.  But I don't follow your argument which says that is a bad thing and why validity should be Level 2.  Really, we have no idea how any SC impact process at all.

> But, if we put validity at L1, our future test based on wcag 2.0 will 
> conclude that every, even trivially, invalid pages and sites would be 
> not accessible, even if they wouldn't be.

Presumably we already conclude that trivially non-conformant pages (say a missing ALT on decorative gif) are inaccessible.  I don't follow the reasoning that hold validity to a higher standard than this.

There is good reason the 508 E&IT accessibility standards never mention the word "accessible" in the standards themselves.
Received on Thursday, 10 November 2005 14:13:58 GMT

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