As an ex eye professional I feel that Doc Drew's post(s) on this are spot on. I think that I have previously made a post or two concerning vision and shooting and about the very large amount of "information" put out by so-called "experts" on this matter. Some of this "advice" and "explanation" comes from some very well known individuals.

His explanation about depth perception and judging distance is particularly good and easily understood by the layman. As he explains, BINOCULAR vision is extremely important for depth perception for ranges UP TO about 20 feet or so. Beyond that distance it essentially makes zero difference whether using MONOCULAR (one eye) or BINOCULAR (both eye) vision. Unfortunately I can verify that this is true due to the fact that I was blinded in one eye 13 years ago. And of course the affected eye was my master eye which forced me to learn to shoot from the opposite side which is another story. (Need help with that? I've got answers, haha.)

Very close (arm's length) depth perception is terrible. Examples would be threading a needle, using tools, pouring liquids, pushing buttons at the gas pump and even something as simple as applying tooth paste to a tooth brush requires a lot of effort. At a bigger distance like parking a vehicle? Extremely difficult to determine if I am six inches or three feet from an object in front. Same with mirrors pulling into a garage. Again, get beyond the approximate 20 foot range and the problem totally disappears. In other words, judging target distance with one eye only is unaffected. Obtaining a driver's license is a non-issue. In fact I can still hold a 1st Class FAA Airman's Medical for my ATP certificate.

I did and do notice that processing visual information was slower. Initially there was a noticeable difference which with time has effectively disappeared for the most as far as I am aware. An example of this would be trying to pick a single out on a Bobwhite covey rise! Now that I do notice! Actual visual acuity in the remaining eye is totally unchanged, still 20/15. However, using TWO eyes with good vision is simply far more effective because that's the way our total visual system is designed to function. My take from all of this is that if you have two normally functioning eyes use them BOTH. And it goes without saying.....PROTECT them.