Re: Heading structure with 1.3.1 Info and Relationships and 2.4.1 Bypass Block

1.3.1 Info and Relationships: Information, structure, and relationships 
conveyed through presentation can be programmatically determined or are 
available in text. (Level A) 

1. I do not believe skipping a heading level is an issue for assistive 
software users any more than it is for a non-assistive software user.  In 
other words, it is an equal usability issue for everyone, but not a 1.3.1 
success failure. 

2. I agree that headings (H1-H6) should be used structurally as the HTML 
markup language semantics intended them to be used, but 1.3.1 does not 
require the use of headings, does not required that headings be used all 
the time in all content, nor that when heading are used that they be used 
sequentially, nor that there only be one and only one heading level 1 per 
page.

3. 1.3.1 doesn't require that presentation include structure, but that if 
and when it does present structure and relationships through presentation, 
that the same information is available through mark-up (or available in 
text). 

If we want to "add" a new success criteria that requires that if and when 
heading levels are used, that they be used sequentially, but we have to 
allow for many situations that are consistent with the intent of the HTML 
specification.  For example:
 
a. Page that is quoting a part of a page that doesn't include a heading 
level 1 should be allowed.  In other words starting with a heading level 2 
or 3.

b. Heading level 2 can follow a heading 3 or 4 if it is going back up a 
level.  For example:
        H1
                H2
                        H3
                H2
                        H3
                                H4
                H2

c.  Page that doesn't include any heading level 3's, but uses a consistent 
heading level 4 for all footers across a set of pages should be allowed. 
In other words, it is OK to skip a heading level on a page in some 
situations. 

So, with these examples we can begin to see why the working group could 
NOT reach consensus to ALWAYS require the use of headings, ALWAYS starting 
heading level 1 and NEVER skipping a heading level. 
___________
Regards,
Phill Jenkins
pjenkins@us.ibm.com
Senior Engineer & Accessibility Executive
IBM Research Accessibility
ibm.com/able
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