Earlier quoted context omitted.
FWIW this is really not true. (The bit about stereo vision being required to see 3D.) When I was in college I was fairly decent on the ping pong table, call it high amateur. I also have very very bad vision - -5 diopters in one eye and -6 in the other. At the time I wore contacts and I was also really really poor. At some point I lost one of my contacts and for six months I was effectively blind in one eye for the pu…
Did you play with only one eye open, or just one contact lens? I have worse vision than you (-8.0, -7.50), and I know that I can still function with just one lens in of needed. You definitely still have stereo vision even if one input is blurred. Your brain does quite a bit of compensation, and I can imagine if you operated this way for months that your brain would be even better at assimilating the noisy information…
It turns out that stereovision is the least important of several depth cues humans use, and is only really effective out maybe 10 feet or so--beyond that the parallax is too small to give much useful info, and we rely on apparent size, relative motion, surrounding context, etc. I can catch a ball just fine, as an adult.
It's really only an issue within arm's reach, and then only when I'm distracted. Occasionally I'll reach for something without paying attention and miss by, like, a foot. Also, I can't use 3D glasses. (With the new polarized kind I can at least wear them and see a normal 2D movie. With the old red/blue kind, everything would be either red or blue, depending on which eye I was using.)