Never had a gun when I was a kid.
However, from my fairly extensive experience in the gopher fields of southern Alberta, I can tell you that a single shot will improve your shooting over a semi-auto.
It isn't in the rifle or the principles of marksmanship. It is all in the psychology of knowing you have only one bullet to make the shot vs thinking you have a bunch more shots if the first one isn't right. That subconscious thought tends to make the semi-auto shooter more careless with his shooting and thus results in more misses.
I have seen it with novices and experts alike. I have seen it in myself. Which is why I refuse to use a semi-auto shooting gophers.
A few years ago I met a guy who was a died in the wool 10/22 marksman. This guy was good. In the time it would take me to cycle the action, he could chase down a running gopher and kill it, which was a bit frustrating for me. We spent the entire summer shooting together, him with his g/d semi-auto and me with my heavy single shot target rifle. Just about the time I was ready to concede defeat and go to the dark side, he admitted that he was jealous of my kill rate and ability to whack gophers at extended ranges with only one or two rounds and he would be getting a single shot target rifle.
Since that time we have known people who would be lucky to tally a 10% kill rate with their semi-autos. These guys just go out and blast and blast and blast rounds downrange till they hit something. Their thumbs going bloody from loading mags.
Where we, with our single shots, would routinely rack up kill rates in the 70% range.
The semi-auto guys are the ones bragging about going through a brick or two in a day's shooting but the truth is they are only killing 50-100 gophers in the process. Where, with a single shot, I can shoot a measly two boxes to get the same number of kills. If I go through a brick of ammo in a day the body count will be closer to 300-350. Which is more satisfying?
It does make a difference between knowing you have one single shot to get the job done vs having a magfull of rounds at your fingertip. The first promotes marksmanship where the second promotes ammo wastage.