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Fwd: ISSUE-30 counter-proposal (longdesc="")

From: Laura Carlson <laura.lee.carlson@gmail.com>
Date: Sun, 14 Feb 2010 04:19:17 -0600
Message-ID: <1c8dbcaa1002140219o7c77bcb8g58f8d8b58b774932@mail.gmail.com>
To: HTML Accessibility Task Force <public-html-a11y@w3.org>, Charles McCathieNevile <chaals@opera.com>
Hello Everyone,

For your information Ian's Zero Edit Counter Change Proposal for
longdesc is in the forwarded message below and at:

This is in response to Chaal's longdesc Change Proposal:

I added this counter proposal to the Accessibility Change Proposal
Status Wiki page:

-- Forwarded message --
From: Ian Hickson <ian@hixie.ch>
Date: Sun, 14 Feb 2010 08:54:07 +0000 (UTC)
Subject: ISSUE-30 counter-proposal
To: public-html@w3.org

Here's a counter-proposal for ISSUE-30:

== Summary ==

The longdesc="" attribute does not improve accessibility in practice and
should not be included in the language.

== Rationale ==

Several studies have been performed. They have shown that:

* The longdesc="" attribute is extremely rarely used (on the order of 0.1%
in one study). [http://blog.whatwg.org/the-longdesc-lottery]
* When used, longdesc="" is extremely rarely used correctly (over 99% were
incorrect in a study that only caught the most obvious errors
[http://blog.whatwg.org/the-longdesc-lottery]; the correct values were
below the threshold of statistical significance on another study that
examined each longdesc="" by hand
* Most users (more than 90%) don't want the interaction model that
longdesc="" implies.
* Users that try to use longdesc="" find it doesn't work ("Who uses this
kind of thing? In my experience [...] it just didn't work. There was no
description.") [http://www.cfit.ie/html5_video/Longdesc_IDC.wmv].

Furthermore, there already exist a number of alternative mechanisms for
providing information to users without using longdesc="", such as simply
including the information inline, providing explicit links to long
descriptions, and using ARIA attributes such as aria-describedby="".

Including the longdesc="" attribute in the language therefore seems like a
poor design decision.

== Details ==

No change to the spec.

== Impact ==

=== Positive Effects ===

* Stops authors from spending time trying to use a feature that they don't
understand and that users don't want.
* Encourages authors to include suitable information in an alternative
form that is more likely to be accurate.
* Results in better overall accessibility on the long term.

=== Negative Effects ===

* ?

=== Conformance Classes Changes ===

No change to spec.

This would not affect existing ATs and user agents, as they can continue
to support longdesc="" if compatibility with some set of documents where
it is used correctly is desired. In practice, removing support is likely
to either not be noticed (some users don't know the feature exists) or
actually improve matters (given how poorly the feature is used in practice
on the Web).

ARIA provides a number of alternative mechanisms that are currently not
poisoned by existing content and that fit better into the kind of
interaction model desired by users (according to the survey cited above).
For example, aria-describedby="" allows an image to be related to in-page
descriptive content.

=== Risks ===

* ?

== References ==

Links included inline.

Ian Hickson               U+1047E                )\._.,--....,'``.    fL
http://ln.hixie.ch/       U+263A                /,   _.. \   _\  ;`._ ,.
Things that are impossible just take longer.   `._.-(,_..'--(,_..'`-.;.'

-- End forwarded message --

Best Regards,
Laura L. Carlson
Received on Sunday, 14 February 2010 10:19:46 UTC

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