Re: HTML Action Item 54 - ...draft text for HTML 5 spec to require producers/authors to include @alt on img elements.

Steven Faulkner wrote:
> hi J graham,
> 
>  >That doesn't seem so far away from many other non-machine checkable
>> conformance requirements in the spec.
> 
> 
> Seems like a good reason to revisit any examples of requirements in
> the spec and provide requirements that are practical to independently
> test conformance , rather than make requirements that cannot be tested
> by anybody other than the author.

That would appear to preclude requirements such as:
"The alt attribute [...] must contain a text alternative that serves the
equivalent purpose as the image. What is to be considered an equivalent purpose,
depends on the way an image is used."[1]

Since only the original author can be a definitive judge of the purpose of the
image.

I would argue that requiring knowledge of author intent does not prevent a
conformance requirement being useful; such requirements can still increase the 
fraction of authors who do something well; this is the social engineering aspect 
of conformance requirements that I have previously discussed [2]. It does 
prevent services with no access to out-of-band information handing out badges to 
proclaim conformance, but it's not clear to me what the value of such badges is 
supposed to be, especially in the case where the conformance requirements have 
been watered down to meet the the capabilities of badge-providers.

What _is_ dangerous is trying to encourage certain practices that require 
knowledge of the author's intent using conformance requirements that do not. In 
this case it is likely that the author will optimise to the letter of 
conformance and fail to actually achieve the goal that the spec authors had in mind.


[1] http://esw.w3.org/topic/HTML/Action54AltAttribute
[2] http://lists.w3.org/Archives/Public/public-html/2008May/0242.html

-- 
"Eternity's a terrible thought. I mean, where's it all going to end?"
  -- Tom Stoppard, Rosencrantz and Guildenstern are Dead

Received on Wednesday, 21 May 2008 17:25:45 UTC