I am not a professional web developer, but I used LAMP to make a decent size website using standards conformant XHTML/CSS without table hacks with PHP and MySQL for forms when I was in high school. I wrote the markup by hand, so I made certain to place content first so that 56k modems would load it quickly and web browsers for the the blind would not read navigation bars before the actual content. At the time, I assumed that JavaScript was not always available because people eithet either turned it off to eliminate the Javascript engine as an an exploit vector or were using browsers that did not support it because they were blind.

Consequently, I considered requiring JavaScript for a webpage to load properly to be bad practice. Even if I assume JavaScript is everywhere, I have yet to hear of how one would make things dependent on it accessible to the blind. I know that people will make webpages that require it regardless of whether the blind can view them or not, but I still feel that is bad practice.