Proposed requirement: specification should provide enough detail to handle Web content

I have another proposed requirement that I've been meaning to write
up for a while.  This fits in with the "WellDefinedBehavior" item on
the wiki [1], but it's somewhat more strongly stated.

I think the HTML specification should specify HTML to the level of
detail necessary to handle Web content.

In order to keep the information on the Web freely accessible (to
whoever wants to write tools to look at that information) and to
encourage competition in software dealing with Web content
(browsers, editors, etc.) which in turn tends to improve the quality
of that software, I think that if a particular behavior is needed to
handle Web content correctly, it should be described in some freely
implementable specification.  That's a pretty strong statement of
rationale that I think some others may not agree with in general.

However, I wonder if we could get agreement on it as it applies to
HTML.  This would mean that one of these behaviors that needs to be
described (based on my previous paragraph) relates to the handling
of HTML, it should be described in the HTML specification.  In HTML
(as in other specifications with multiple implementations), doing
this is likely to improve interoperability, which improves the
experience of both authors and users (writers and readers).

What does this mean in practice?  I see two things:

1. We should try to describe as much of this behavior as we can.  We
   probably won't get all of it, but that doesn't mean we shouldn't
   try to be as complete as reasonably possible.

2. We should not accept a "leave things undefined" compromise when
   the missing definition is broad enough that some definitions
   would handle existing (or future?) Web content as intended and
   some would break it.  (Of course, there will sometimes be
   difficult cases where the existing content goes both ways.)  We
   should instead at the very least narrow the definition to a set
   of things that do handle existing Web content correctly.

-David

[1] http://esw.w3.org/topic/HTML/ProposedDesignPrinciples , which
    currently says:
      WellDefinedBehavior: Prefer to clearly define behavior that
      content authors could rely on, in preference to vague or
      implementation-defined behavior. This way, it is easier to
      author content that works in a variety of user agents.
      However, implementations should still be free to make
      improvements in areas such as user interface and quality of
      rendering.

-- 
L. David Baron                                <URL: http://dbaron.org/ >
           Technical Lead, Layout & CSS, Mozilla Corporation