Even with age, you can use irons, you simply have to have the glasses corrected...
And most don't understand that with irons you can only focus on one focal plane at a time.
Hence the most important thing is front sight. It helps to have the target clear and the rear clear to, but its not needed.
I had to shoot without correction with pistols becasue my eye could and would focus on the target paper at 25 yards, and gave horrible groups, NEEDED the target to stay blurry.
When in doubt put a peep on the rear, and even an aperture in the front.
As to success... lets just say paper targets you get used to, but with game, I've shot stuff so far away that most would call you a liar, luckily my longest shot with irons on small deer was witnessed by at least 3 others in the truck at the time..
YOu have to have the desire though, especially with irons, to learn how to use them, whats important and how to trust the sights and your eyes. Your eyes are capable of MUCH more than most give them credit for.
And before someone claims I have good vision, I had to have correction in my teens, and its never gotten better, only worse, and I didn't start shooting a LOT of irons until I was in my 30s, and carried on until appx 42 with irons in competition.
Having shot same with folks in their 70s plus, its still possible even as eyes age.
