Re: Does 5.1 absolutely require TH?

> The table is definitely a data-table with contents of a cells being related to cell contents in adjacent cells.

Sailesh, where are you taking this definition from?  I think I like it.
Sailesh: I have always maintained this and had proposed to WCAG-WG in one of my  posts. And just a few weeks ago I read an extension to that to define a layout table- if a cell can be moved around such that it does not affect the  comprehension of the table, then it is a layout table.

But the discussion of determination of data table versus layout table is off-topic.
-- Either that, or said determination IS the answer to my question.  I am not sure!
Sailesh: The checkpoint reads: 5.1 For data tables, identify row and column headers. So till you determine whether your table is a dt or an lt , you can go no further!

I will also remind the group that there is strong traditional that Single-A conformance need not change the default presentation of the page (ALT text and the like being largely invisible).
Sailesh: Where did you  read this   _need not change the default presentation _ stuff in WCAG 1 and related docs? WCAG 2 is moving that way. But definition of Priority   levels in WCAG 1 do not suggest that.

For the purposes of this discussion, let's assume I am only interested in what I must do, the minimal.  But that I am committed to Single-A conformance.
So, does 5.1 absolutely require TH?
Sailesh: Absolutely.  A data table greater than 2 by 2  needs th if the author intends the user to interpret and read the table as a data table.

We all agree that headers would be nice.  But are they required?  John says no (reluctantly).  Can anyone provide me some evidence to the contrary?
Sailesh: I gave you an example  of an accessibility problem in my first mail on the subject and was seconded by Jennifer. 
Sailesh Panchang
Senior Accessibility Engineer 
Deque Systems,11180  Sunrise Valley Drive, 
4th Floor, Reston VA 20191
Tel: 703-225-0380 Extension 105 
E-mail: sailesh.panchang@deque.com
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