I’m pretty sure that the odd offscreen label won’t cause any major issues but two or more ‘hidden’ in this manner could.

If you want to have a look at offscreen positioning in general, have a look at the skip links on Accessites.

I think this is where some of the confusion can arise when trying to define dyslexics as a group. Because the severity and nature of the difficulties varies from one individual to another, it’s very easy to develop a slightly skewed impression of what is, or isn’t, a problem for the group as a whole.

When designing pages, I do think we have to consider those who do have reading problems (who could be classed as the most severely affected) but I also think we have to keep any design changes relatively subtle so as not to negatively impact on other users. As always, I think it comes down to trying to achieve a reasonable balance.

My own personal feeling is that, because visually impaired users have been early adopters of assistive technology and have, very successfully, highlighted the problems that they face, the balance within accessible web design has become somewhat skewed in their direction. This, unfortunately, creates even more problems for many dyslexic users. If we can raise awareness of the issues that dyslexics face generally, we might be able to re-adjust that balance somewhat - hopefully without creating problems elsewhwere.