- From: Gregg Vanderheiden <gv@trace.wisc.edu>
- Date: Sat, 5 Nov 2005 15:05:46 -0600
- To: "'Gez Lemon'" <gez.lemon@gmail.com>
- Cc: <w3c-wai-gl@w3.org>
Thanks Gez Anyone - any others? Gregg -- ------------------------------ 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 Gez Lemon Sent: Friday, November 04, 2005 7:37 PM To: Gregg Vanderheiden Cc: w3c-wai-gl@w3.org Subject: Re: Summary of arguements FOR validity -- and another against -- and a third of alternatives Hi Gregg, I've tried to be as objective as I can, but it would be helpful if people could go through the list and ensure that I've represented their viewpoint fairly and accurately, and ensure I haven't missed any important points - particularly as I am biased towards requiring validity in the guidelines. On 04/11/05, Gregg Vanderheiden <gv@trace.wisc.edu> wrote: > > > > 1) Can someone give me a list of the arguments FOR including validity. * Validity errors can and sometimes do result in accessibility barriers * Invalid documents are not testable, so it cannot be guaranteed that the final rendering will be accurate for AT * How can elements be programmatically determined if you can't be sure that the content is valid * It is doubtful, and not testable, that other guidelines catch all validity errors that could result in an accessibility barrier * The four principles on which WCAG 2.0 is based require valid code to be testable * Specifications are designed with accessibility in mind, so there should be no need for invalidity * There are always ways to work around issues validly * Invalidly addressing an issue could cause other issues * There is a deep fundamental flaw with a set of standards that proposes to use a baseline concept, but fully rejects embracing basic syntax checking available with the core technologies * Promoting robust and stable long-term standards, even if the face of known issues - which we have every reason to believe will be temporary - is being practical. * Validity is a stable target - if authors follow validity guidelines, OS / browser / plug-in / AT will all improve * Validity has been a requirement in WCAG 1.0, and no one knows of a case where someone has been prosecuted for invalid content * People get prosecuted because they fail to consider others, but for having invalid content * Disrespectful of other specifications, including w3C specifications * Validity offers a solid base on which to build accessibility, and encourages accessibility to be considered from the ground up, and helps safeguard against errors creeping in at a later stage if there is an effort to ensure validity through the project lifecycle. > 2) Now I need someone (else?) to send one of the arguments against. * Additional markup may be necessary to overcome problems that the specification authors were not aware of, and so is not part of the specification, but could improve accessibility * There are other level 1 success criteria that safeguard against accessibility barriers that could be introduced with invalid markup * Too difficult to achieve because of the tools that generate markup * Some developers think they're being clever creating accessible content, but they aren't (cargo cult) * Not all validation errors are of the same level of importance to accessibility * It is possible to have invalid markup that is accessible * It is possible to have valid markup that is inaccessible * The people who wrote the specification don't really want anyone to follow it * Having validity in the document means that the document will not be adopted * Testability is easily achievable with invalid content by running it through an assistive device (observe reality) * Legislation could result in people being prosecuted for invalid markup * Even though there has never been a case of legislation against validity, there could be in the future * Legislators can't reasonably be expected to read a document that they're using for legislation to determine which parts they intend to apply * We're shooting ourselves in the head > 3) Now if someone can summarize any alternatives or variations I wouldn't support them all, but for completion: * Validity at level 1 * Validity at level 2, with techniques that address validity in the techniques for appropriate success criterion * Watered down version of validity at level 1, with validity a requirement at level 3 * Validity completely removed from the guidelines (with a foreword in the document explaining the importance of validity), and address validity in the techniques for appropriate success criterion Best regards, Gez -- _____________________________ Supplement your vitamins http://juicystudio.com
Received on Saturday, 5 November 2005 21:05:52 UTC