Ensure sufficient guidance regarding impact of roles on semantics associated with elements

[joanmarie]

Some concrete examples and related discussions/concerns:

• <table role="log">...</table> will stop being a table (and thus lose screen-reader table presentation and navigation commands): Mozilla bug, related public-aria list thread starter, and Matt's on-list response, with a proposed solultion.
• "Weak" landmarks in Gecko in order to ensure scenarios like <ul role="navigation">...</ul> remain exposed as a list (i.e. and NOT exposed as a landmark, contrary to what is stated as the mapping in the Core AAM 1.1): Mozilla bug with thoughts from James Teh and me.

The solution which strikes me as the best way to ensure interoperability as well as buy-in from user agent and screen reader implementors is to ensure authors don't apply roles to elements with associated semantics and screen reader presentation/navigation. In other words, as Matt had suggested in his on-list response:

If an author wants to make a log table use <div role="log"><table></table></log>.

Seems like a job for Authoring Practices. 😄

[mcking65]

I have been planning on adding an introductory section that could some of the most important fundamentals/dangers of ARIA ... I will accelerate in response to this need.

[mcking65]

@joanmarie, @jcsteh, @MarcoZehe,

Today I added a proposed draft of a new
Read Me First
section to APG. I am curious to know if it adequately addresses concerns expressed in
Mozilla bug 1407287.

[mcking65]

Work on this is complete and has been reviewed in issue 482. If the resolution is not adequate, please feel free to reopen.