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Comments- Metadata and WCAG

From: Liddy Nevile <liddy@sunriseresearch.org>
Date: Fri, 9 Nov 2007 10:51:13 +1100
Message-Id: <9720AC9F-D78A-45D2-9C08-6CFC4BF50C5B@sunriseresearch.org>
To: public-comments-wcag20@w3.org


Comment 1: metadata and WCAG 2.0
Source: http://lists.w3.org/Archives/Public/public-comments- 
wcag20/2007May/0137.html
(Issue ID: 1957)

With respect to the following, I have this to say:

First, thank you for your time and attention.

I am very pleased that metadata has been included in the  
specifications and am sure this will prove to be a very useful addition.

  I wish to make two final points for consideration, possibly at some  
future date:

(1) Any resource that is not described with metadata must be accessed
in order to discover what it is about and how it works and can be
accessed. This places a burden on users at selection time, if it is
being accessed other than because it is already known to be what the
user wants, and so it makes access to the resource less flexible and
potentially distracting (as is the case when it is not what the user
wants but they have had to retrieve it to discover this).

(2) When the means of accessibility is not a static, conformant page
but rather a dynamic compilation of components, as is common with Web
2.0, and as may be achieved by a service that provides resources to
match a user's personal needs and preferences (using components that
in themselves and in isolation may not be fully conformant), without  
appropriate metadata, the service agent can not know what components
to compile to suit the user. In this case, such a service that
potentially provides a higher than usual form of accessibility would
be denied. It seems odd to allow this situation to exist.

Liddy Nevile.

---------------------------------------------
Response from Working Group:
---------------------------------------------

The working group recognizes that proposed metadata structure can
potentially be beneficial to people with disabilities, technology
developers, and content authors.   We have added metadata into WCAG in
a couple of ways, but we are not adding a success criteria requiring
metadata.  It turns out that there two flaws in the logic that
counterindicate this.

1) If content meets all the other SC already (including using metadata
to meet the other SC) then adding a new SC requiring additional (not
required for conformance) alternatives be linked by metadata is
requiring metadata links to do things that aren't required.

2) If content met the other SC but the author wanted to provide a
special alternate version (which did NOT meet WCAG but did provide a
particularly accessible version for a particular disability) and the
author didn't use metadata to link to it (the author provided links on
the page instead) then the page would fail even though the new content
wasn't needed to meet WCAG and even though there was a self
explanatory link right there that would take a user to the alternate
version.

Our conclusion was that Metadata was a very powerful technique for
doing certain things but that, like other technologies, we didn't want
to specify it too tightly in the SC.  Instead we would like to focus
on it in the techniques to meet other success criteria.

What we have done therefore is the following.

http://www.w3.org/WAI/GL/WCAG20/WD-UNDERSTANDING-WCAG20-20071102/ 
appendixC.html
Received on Thursday, 8 November 2007 23:51:26 GMT

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