You aren’t quite right in thinking that this is only used for image replacement though. It’s also used to display and collapse menus where, if screen readers ignored the “display: none” command, their users would have the dubious treat of having to read every second and third level link on a page, even though they aren’t visible. It’s also used for showing and hiding FAQ answers on some pages, and because that technique is used, rather than in-page links, the creen reader would need to read through all unwanted answers until they reach the one they want.

Since then, though, I’ve been wondering — WHY do screen reader applications even look at the CSS file?

It seems to me that CSS files are intended for visual formatting, and carry no content. So why isn’t the default setting on screen readers to ignore the CSS file altogether?

(And, anticipating one possible answer — that people who are visually impaired but not entirely blind may want stylesheets to load — then in that case why not have a built-in option to ignore the “display: none” specification in the stylesheet? It is rarely used for anything BUT image replacement.)

Also IE treats alt text as tool tips where as other browsers rightly don’t.

I know when people use such transparant images for layout spacing, their alt-text is read out.

http://www.access-matters.com/screen-reader-test-results/

Window Eyes 4.5 and 5 with IE 6 seem to be the most problematic with all the methods tested. Methods 8, 9 and 11 seem to have the broadest screen reader reach.