Interesting information. Major downside to it is this. Real world shooting, you're not gonna have a nice, bright orange dot to look at with blurred yet defined edges.
For me, handguns are for closer work. If you're gonna hunt with them and so forth, that's what scopes are for. And the problem goes away. But back to the close-up work, my priority is keeping my eye on the target. Louis L'Amour said more than once that snap shooting is like pointing your finger. You point the gun naturally as you would a finger and it works most of the time. In a real shooting emergency, you're not gonna have all that much time to look down your sights, think about it, get optimal alignment, then pull the trigger. You might be dead or badly injured by that time. Besides, if your first shot or two doesn't hit home, at least it usually has the benefit of causing your opponent to take cover and break his concentration. Just my opinion.
Lyman (and maybe others) used to offer a little diopter that you could stick on your eyeglasses. Basically, it would cause your eye to have a more narrow focus, therefore increasing the focal length. Like an F stop on a camera. I've used one before with success until I lost it. I should get another one. They're good for range work. But you're probably not gonna have one in a shoot-out.