I agree that a website for a product like this should have exemplary accessibility. The heuristic I'd use in a screen reader is as follows: if a user activates

I agree that a website for a product like this should have exemplary accessibility. The heuristic I'd use in a screen reader is as follows: if a user activates a link and a new element becomes visible but nothing else happens within half a second or so, read the contents of that element as if it were a newly loaded page. FWIW for anyone else reading this thread, ndarilek and I have each developed a screen reader (on Android and Windows, respectively).