I did not know that, about nystagmus.

I do find that when I have dilation drops in, my focus-point changes: I become more farsighted (i.e., my vision is better) than it actually is. Which is pretty strange, and possibly a precursor to how I will spend my middle years: holding the book away from my face to read. The other fun side-effect of course is looking like a crazed possum for several hours. (I've never tried the reversal drops.) It's the kind of cool that, I'm just as happy it happens only once a year.