I would just like to comment that very smart kids might not demonstrate a vision issue in reading level. My son's reading level is about a grade or two over his age but he reads very slowly. As his eyes improve, it's not so much his reading level as his reading speed that's improving. Isn't that weird?
Also, I have similar vision issues (letters jump up and down) and I read at the college level. I have a technique where I use my finger and I also open my eyes wide and then, scrunch them down to refresh them. It's just my little secret.
I think one way that you can tell if his vision is still a problem is sort of spying on him. Look for squinting, funny blinking, head cocked in a funny direction when he begins reading. Also, another clue is sudden tiredness after reading a bit.
I'm no expert, by the way. This is all based on personal experience.
