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Re: FW: Questions and proposed approaches for Baseline Specifics

From: Jason White <jasonw@ariel.its.unimelb.edu.au>
Date: Fri, 8 Sep 2006 19:51:47 +1000 (EST)
To: Web Content Accessibility Guidelines <w3c-wai-gl@w3.org>
Message-ID: <Pine.GSO.4.58.0609071450480.21794@ariel.its.unimelb.edu.au>

On Wed, 6 Sep 2006, Gregg Vanderheiden wrote:

> 1) What do we mean by a technology.  Do we mean a particular specification
> or a general type?
I think a particular specification is what is meant, or at most a set of
specifications, being different versions of the technology There must be
enough information specified in the baseline to allow a content evaluator
to determine whether the guidelines have been met at a specified level,
assuming only support for technologies in the baseline.
> 2) What if there is an extension of a technology that someone developed.  Is
> it included?  What about modules that extend a technology?  If they are
> supported by User agents including AT - shouldn't they be part of baseline?
> Are they?
If the content relies upon them in implementing any of the success
criteria then presumably the author would have to specify them in the
baseline. After all, the content assumes that they are supported, and
unless an alternative is provided, relies on them for purposes of
conformance. On the other hand, if the extensions don't affect conformance
at the claimed level then they aren't part of the baseline, since in that
case the content can be used and will be as accessible as has been claimed
even when read by UA's that don't support the extensions.
> 3) What if there are features of a technology that are NOT supported by AT.
> And if using them would make a page (or that part of the page) inaccessible?
> Can they be used WITHOUT providing an accessible alternative?
That depends on whether they are included in the baseline, and whether, if
support for them is assumed, the content meets all the success criteria at
the claimed level. Nothing stops someone from including such technologies
in the baseline, unless it is true that, were they supported, the content
implemented using them still couldn't bmeet the success criteria. However,
such a baseline would be a badly chosen baseline. If your question is
whether such technologies should be included in the baseline then the
answer is "no". If it is whether they can be included in one, then that
depends on what would be the situation if the technologies were supported
by accessible UA's. I am sure there are (in principle and in practice)
technologies that simply can't be put into baselines on the ground that
they don't have the required features to enable content developed using
them to be accessible (i.e., the content can't meet one or more level 1

Actually I am a little confused here. reading Gregg's proposed answers to
these questions I notice a lot of discussion regarding baselines to be
written/proposed by the working group and used in techniques documents. I
think it is very important to distinguish between (a) what can and must be
specified in a baseline according to the guidelines; and (b)what
constitutes a good baseline, what baselines the working group itself will
offer in non-normative documents and how these baselines affect

I am sure the context in which the three questions arose, with which I'm
not acquainted, would help to clarify what is needed, i.e., clarification
of what the guidelines will say about baselines, or clarification of what
constitutes a good baseline, how they will be formulated and their
relationship to the techniques/failure cases, etc., in techniques
Received on Friday, 8 September 2006 09:52:11 UTC

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