Re: Very large print = refresh-able braille

Alastair, I don't see why your comments are devil's advocate. If authors
design with the possibility of linearization in mind then the browser
facilities should do the job. Did I miss something? Look at my new concept
for Linearization, I think it can apply to applications and pages, but it
needs work: https://github.com/w3c/wcag21/issues/174 . It is a little
difficult.

Here is my issue with the current approach. I doubt that WCAG 2.0 could
have been accepted if braille users did not have access to braille. Access
to large print, is just as necessary, to low vision for the same cognitive
reasons. However, large print appears to be negotiable.

Without access to a self paced reading medium most people cannot read
extremely difficult material, the kind of material people employ you to
read. So, people with low vision cannot complete college and get
professional jobs.

Now enlargement without word wrapping has two fatal problems. 1) It
requires an extraordinary amount of scrolling and cognitive adjustments,
and 2) The size of the word buffer is small. The LP buffer for enlargement
without word wrapping is less than 40 characters for 400%, 500% and 600%.
On my screen now, at 400% I get 32 characters on the longest line.  That
would be for 20/80. At 500% the longest line has 25 characters. That is for
20/100. At 600%  (20/120) we get 20 characters. Without word wrapping the
screen does not hold enough characters to support short term memory.

With word wrapping we get 256, 125 and 80 character screens respectively.
That character buffer size is enough to support self paced reading. These
numbers were on my big screen (34"). On my 13" the buffers are smaller, but
practical for word wrapped material.

The reason that the character buffer size is so much smaller for non-wrap
versus wrap is that only one line on any non-wrap page has meaning. The
rest of the characters do not form a meaningful sequence.  On a wrapped
screen all characters count.

The problem is that self paced reading is critical for professional
reading, because the material takes careful analysis and memory support.
Right now braille users have access to effective self paced reading to pair
with text-to-speech. Most people with low vision except for the few on our
WCAG committees only have access to voice.

If we do not provide enlargement with word wrapping, then we are saying
that the best the web can provide is a non-professional level of access for
people with low vision. Harmonization will extent that poor access to
e-books, magazines and other important digital documents. I am not sure
that there is any definition of accessibility where that limitation fits.



The central fact is this if refreshable braille is necessary and important
enough to require developer pre-planning then so is large  print, because
they serve the same function. One that enlargement without word wrapping
cannot satisfy.