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Re: 48-Hour Consensus Call: InstateLongdesc CP Update

From: Silvia Pfeiffer <silviapfeiffer1@gmail.com>
Date: Mon, 24 Sep 2012 22:23:39 +1000
Message-ID: <CAHp8n2=quXLWiLzs1mqDC233oD46HV5-Mt8JxYLkPZf6RurTYw@mail.gmail.com>
To: Charles McCathie Nevile <chaals@yandex-team.ru>
Cc: Laura Carlson <laura.lee.carlson@gmail.com>, Geoff Freed <geoff_freed@wgbh.org>, HTML Accessibility Task Force <public-html-a11y@w3.org>
Hi Charles,

On Mon, Sep 24, 2012 at 8:58 PM, Charles McCathie Nevile
<chaals@yandex-team.ru> wrote:
> Hi Silvia,
> SEO, repeating the mistaktes, old aldvice doesn't die,
> On Sun, 23 Sep 2012 02:41:56 +0200, Silvia Pfeiffer
> <silviapfeiffer1@gmail.com> wrote:
>> On Sun, Sep 23, 2012 at 5:51 AM, Laura Carlson
>>> longdesc is experiencing increased usage in the wild
>>> http://lists.w3.org/Archives/Public/www-archive/2012Sep/att-0025/comments-mt.html#increasedusage
> [...]
>> Interestingly, you data actually confirms the message that I just sent
>> on another thread [1] about moving to @aria-describedat. I would think
>> that all of these institutions that are supportive of accessibility
>> and are using @longdesc in the correct way for this purpose would
>> accept moving to use @aria-describedat if we encouraged them to do so.
>> In this way, the vast pollution of @longdesc values that we see in the
>> wild would be replaced by only clean and accurate use of
>> @aria-describedat . It would make it easier for tools to identify
>> sites that have appropriate and usable long text alternatives, since
>> you can just search for @aria-describedat and know you will get good
>> results, rather than searching for @longdesc and having to wade
>> through vast numbers of misuses.
> Actually, I doubt that will be true. There are several factors that I
> believe will lead to aria-describedat having significant pollution:
> 1. It is invisible metadata. While this is only an issue for content
> producers whose workflow isn't sufficient for quality output, there are many
> of those. It seems unlikely this problem will completely disappear.

Basically all @aria-* attributes are invisible without the use of AT,
but "visible" with AT. I think that was never clear for @longdesc. We
can fix it for a new attribute.

> 2. SEO is big business. Many people would rather use accessibility features
> for SEO than for improving accessibility. As an example, http://dilbert.com
> seems to do this with the alt attribute for the comic of the day - and I
> believe this is still a common practice.

Agreed, though I think you may over-estimate the use of @alt for SEO
(see http://www.seologic.com/faq/alt-tags).

In any case, the amount of polluted @longdesc will make it impossible
to use @longdesc by search engines for a very long time, and therefore
the impact on SEO won't exist. A new attribute can likely gain the
trust of search engines much earlier than @longdesc.

> 3. Longdesc isn't terribly complicated. The original description of longdesc
> for img begins:
> "This attribute specifies a link to a long description of the image. This
> description should supplement the short description provided using the alt
> attribute..."
> While it isn't a perfectly clear specification, I found it difficult to
> understand how reading it could lead to any major confusion. Yet
> demonstrably intelligent people who did read it have reported being
> confused, and it seems almost certain that some people used the attribute
> (and possibly even wrote guidance on using it that others read and believed)
> without actually reading it at all. These mistakes are eternal, and while
> they can be reduced with better naming, clear educational efforts, etc, it
> is very difficult to eliminate them.

These mistakes are eternal for @longdesc, indeed. We have a clear
slate to start from for a new attribute.

> 4. The old guidance, and wealth of discussion, will hang around.  And people
> will find it, and follow it. Or continue relying on what they have already
> learned. Which will lead to some people using longdesc instead of
> describedat or whatever a replacement is called. While this isn't pollution
> per se, it is reducing the signal:noise ratio for describedat, by reducing
> the signal.

It seems that everyone who understands @longdesc also understands
accessibility and is mostly creating long descriptions for
accessibility reasons. These content producers are listening to us and
are open to new advice. Those that have mis-used and polluted the
general Internet won't fix their use (and thus the signal:noise ratio
will continue to be high for @longdesc). I have much higher hopes of
getting a new attribute's use correct from the start with better
descriptions and advice and by focusing it on accessibility use.

> All of these factors can be mitigated somewhat, and I expect enhancing
> longdesc (whether we change the name or not) will lead to an increase in the
> signal:noise ratio. But I believe that there will be a lot of noise - just
> as there is with alt.

The problems are a lot less likely for an attribute starting with @aria- .

> The alt attribute is almost certainly the best-known
> "accessibility-specific" (at least mostly, in popular perception) feature,
> and one of the most generally applicable to web content. After more than a
> decade of massive education, regulation and motivation for improvement, I
> would make a large bet that the majority of Web content has badly polluted
> alt attributes. In addition, many people (including me) believe that it has
> some nasty limitations that cause real-world problems. Yet I hear no serious
> suggestion to replace it, and believe there is strong consensus that it is
> very valuable despite the misuse and lack of use.

In fact, we have @aria-label and @alt for setting an accessible name
for images. While we haven't replaced it, we have added a
aria-specific attribute, too.


Received on Monday, 24 September 2012 12:24:32 UTC

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