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"tableinfo" Change Proposal and status of WCAG2 supporting documents

From: Benjamin Hawkes-Lewis <bhawkeslewis@googlemail.com>
Date: Thu, 4 Mar 2010 09:03:45 +0000
Message-ID: <de4cf6d81003040103t6890d387ke25b89d00fc5578e@mail.gmail.com>
To: xn--mlform-iua@xn--mlform-iua.no
Cc: www-archive@w3.org
Lief

With reference to the HTML5 Change Proposal you've drafted to
introduce a "tableinfo" element:

http://www.w3.org/html/wg/wiki/index.php?title=ChangeProposals/tableInfoProposal&oldid=5010

http://lists.w3.org/Archives/Public/public-html-a11y/2010Mar/0077.html

The distinction may be clear to you, but the proposal as drafted
appears to treat WCAG2 Techniques and Understanding WCAG2 as
though:

   * They are part of the WCAG2 standard.

   * They formally define HTML semantics.

   * They impose conformance requirements on authors.

For example, your change proposal includes the following text
referring to techniques:

   * "How can we also not break WCAG2 H39 and WCAG2 H73?"

   * "H73 requires table summaries to go into a summary='*' not
     because authors eventually would refuse to place such
     content inside the caption elemetn (it doesn't discuss it
     from that angle), but because placing it inside caption
     would break the caption's table identification role, as
     defined in H39."

   * "you break the purpose of the caption – especially as H39
     defines it"

   * "This opening 'permits' authors to break H39."

   * "The removal of summary from HTML5 can also be said to break
     H73. However, since a main purpose of H73 is to avoid that
     authors break H39, it is arguably more fundamental that H39
     is broken."

   * "Authors are currently not permitted to freely place such
     content into the caption – not according to HTML4, and
     certainly not according to H39!"

But this isn't the case. WCAG2 Techniques are not part of any
formal recommendation, cannot define HTML semantics, are
entirely informative (and therefore impose no author conformance
requirements), and are an ongoing draft published without
W3C endorsement.

See especially the "Status of the Document" section at:

http://www.w3.org/TR/2008/NOTE-WCAG20-TECHS-20081211/

> This is a Working Group Note "Techniques for WCAG 2.0". These
> techniques are produced by the Web Content Accessibility
> Guidelines Working Group to provide guidance about how to
> conform to the Web Content Accessibility Guidelines (WCAG) 2.0
> Recommendation. Techniques are referenced from Understanding
> WCAG 2.0 and How to Meet WCAG 2.0. Please note that the
> contents of this document are informative (they provide
> guidance), and not normative (they do not set requirements for
> conforming to WCAG 2.0).

[snip]

> Publication as a Working Group Note does not imply endorsement
> by the W3C Membership. This is a draft document and may be
> updated, replaced or obsoleted by other documents at any time.
> It is inappropriate to cite this document as other than work in
> progress.

Similarly, you cite:

http://www.w3.org/TR/2008/NOTE-UNDERSTANDING-WCAG20-20081211/content-structure-separation-programmatic.html

as "WCAG2". It isn't. WCAG2 is the Recommendation here:

http://www.w3.org/TR/WCAG20/

You're quoting from Understanding WCAG2. If we look at the Status
of the Document we find:

> This is a Working Group Note "Understanding WCAG 2.0". The Web
> Content Accessibility Guidelines Working Group considers this
> document to be important for understanding the success criteria
> in the Web Content Accessibility Guidelines (WCAG) 2.0
> Recommendation. Please note that the contents of this document
> are informative (they provide guidance), and not normative
> (they do not set requirements for conforming to WCAG 2.0).

[snip]

> Publication as a Working Group Note does not imply endorsement
> by the W3C Membership. This is a draft document and may be
> updated, replaced or obsoleted by other documents at any time.
> It is inappropriate to cite this document as other than work in
> progress.

Understanding WCAG2 includes a helpful appendix with suggestions
about how to cite WCAG2 and supporting documents:

http://www.w3.org/TR/UNDERSTANDING-WCAG20/appendixA.html

Note especially:

> Techniques, which are listed in Understanding WCAG 2.0 and
described in other supporting documents, are not part of the
normative WCAG 2.0 Recommendation and should not be cited using
the citation for the WCAG 2.0 Recommendation itself. References
to techniques in support documents should be cited separately.

It *is* a big problem (for WCAG2 or HTML5) if HTML5 makes it
impossible for authors to create content that conforms to both
WCAG2 and HTML5. So the question of actual normative conformance
requirements versus informative guidance is significant.

It is not necessarily a big problem (for WCAG2 or HTML5) if HTML5
makes a particular HTML technique inapplicable. However, WCAG2
conformance requirements are not the be all and end of all of
accessibility. There may be HTML features that could increase
accessibility without being required for WCAG2 conformance. These
should be argued for in their own terms, ideally grounded in the
WCAG2 principles (perceptibility, operability, understandability,
and robustness).

So I suggest redrafting your proposal to make it clear where your
argument depends on clear WCAG2 normative requirements, where it
depends on debatable interpretations of those requirements
informed by Understanding WCAG2, and where it depends on wider
purported (and ideally documented) accessibility benefits.

In terms of what WCAG2 does require, I'd note that while WCAG2
does prefer programmatic identification of relationships, this
does not mean every relationship requires its own HTML feature.
For example, a verb has a relationship to the rest of a sentence,
but this does not mean WCAG2 necessitates the addition of
"sentence" and "verb" elements to HTML. There has to be some sort
of judgement call about how useful a particular relationship - or
distinction between relationships - is.

--
Benjamin Hawkes-Lewis
Received on Thursday, 4 March 2010 09:04:18 GMT

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