ARIA WG Guidelines to avoid scope creep (Was: article navigation)

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James Craig wrote:

> PS. "feed" seems a out-of-scope for a 1.1 criteria, does it not? Why is a list of articles in a feed more or less semantic than a list of article outside a feed? Does the end user need to know about the difference? If not, cut it.

I'd like to make a case for extremely critical analysis of which new features make it into ARIA 1.1. My recollection is that the 1.1 release was intended to be a quick errata and oversights release, but we're nearing (over?) 2 years of work already.

I propose creating a list of guidelines the ARIA Working Group can use when considering any new role or feature. The Chair and Staff Contact should use this list of criteria to enforce scope and maintain a reasonable timeline for deliverables. I've started a first draft:

Guideline 1. If the role is a subclass (e.g. checkbox -> switch, or textbox -> searchbox), the ARIA Working Group MUST NOT add the role unless there is a significant *user* benefit to using the subclass role instead of the superclass role. Criteria to determine role worthiness may include (A) commonality of the UI (e.g. switches and search fields are extremely common in mainstream UI) and (B) determination of whether the use of the superclass role causes confusion that is not experienced by a sighted user (e.g. switch labels are often phrased such that "checked/unchecked" statuses are ambiguous to an AT user, but an "on/off" status is understandable. "Bathroom light, checked checkbox" is ambiguous where "Bathroom light, on" is not.)

Guideline 2. The ARIA Working Group SHOULD NOT add a new roles or ARIA features based on speculative future UI behavior of assistive technology. Justification: ARIA 1.0 included some features that were exposed to the API layer to achieve exit criteria, but were never completely implemented by assistive technologies. Exception: The ARIA Working Group MAY propose speculative roles and other ARIA features to support mainstream UI elements that are *unique* to the Web and unlikely to be implemented in native platform UI. (Note: I can't immediately think of a current example that would allow this exception.)

Guideline 3. For minor release numbers (e.g. ARIA 1.1), the ARIA Working Group SHOULD NOT add new features unless there is existing AT support for equivalent native platform features. In order to maintain scope and a reasonable timeline, the ARIA Working Group SHOULD postpone proposing such features until the next major release (e.g. ARIA 2.0). Justification: Exit criteria for minor version spec releases should not be delayed due to expectations of brand new platform API and AT support that could delay the spec for years.

For example, if there is no equivalent to a "feed" role on any native platform, completing it will require the spec editor to solidify prose, then require platform API reviewers to create a new role to match, then require rendering engines to support the new role, then require assistive technologies to support the user feature, before the minor release (e.g. ARIA 1.1) can finally ship. This could add years to the spec process... Not a wise goal for an .1 spec release. In my opinion, the design-by-spec-committee model also flies contrary to the goals of the W3C, which is only chartered to work on cross-platform technical standardization. 

Do other members of the ARIA group think this type of Guidelines list is worth pursuing?

Thanks,
James