Reminds me of the recent research on dyslexia fonts-- the idea is that dyslexic readers are *too good* at mentally rotating objects in their mind-- the same way that we can recognize a cat from any angle because we automatically rotate the image of the cat in three to say, ah, I'm looking at a cat from above or the side or whatever. So the dyslixics see mirror image letters as the same-- i.e. d p b q would be spun around to wreck havoc with reading comprehension.
The dyslexic fonts were tweaked enough to remove most of the symmetries.
Here is the video versionhttp://www.youtube.com/watch?v=VLtYFcHx7ec
Here is a link to the free font (page renders wrong in chrome, but you can still see the font)http://www.pixelscript.net/gilldyslexic/
For normal readers, reading a dyslexic font either speeds you up or slows you down depending on who's reviewing.