Technically speaking that could be true in some cases with longer rifle barrels as long range accuracy is required. If I'm guessing correctly, you are probably referring to the "lapping effect" -- which some rifle marksmen attempt to expedite these days by fire, or hand, lapping their barrels.
With that process, unless the barrel rifling/dimensions are cursed by poor manufacturing, it doesn't do anything more than shorten barrel life. If it were true that a moderately worn pistol barrel shot better, that would indicate that something was very wrong with that barrel to begin with. In my shameless opinion, if a rifle shoots well, there is no good reason on earth to deliberately impart more wear on the rifling.
The quality of the steel, the thickness of the barrel, the precision of the muzzle crown, and the quality of the bedding affect the accuracy of a rifle far far more than polishing the bore with some lapping compound - defective bores being the exception. A cheapo rifle barrel looks like an out of control soda straw when viewed in slow motion. A 1911 barrel looks like a fancy cannon because that's exactly what it is - kinda. There is a big difference in the dynamics and factors needed to achieve the accuracy potential in rifles and pistols.
In this life, what we read, and what our experiences teach us, often conflict. My grandma always said, "Experience is the best teacher." and she had a track record of always being right! In the context of a 4, 5 or 6 inch 1911 barrel with extremely minor tolerance variations, one would never notice the difference of such "moderate" wear at normal pistol shooting distances. Good 1911 barrels will outshoot 99.99 percent of shooters.
Along those same lines, I used to be anal retentive enough to actually slug 1911 barrels - back when I read more than I shot (laugh). I bet I've slugged about 20 of them -- various makes and models. One of the benefits of casting lead bullets is the ability to oversize the bullets slightly to acheive a proper obturation to the barrel rifling. Over the years, and in the context of 1911 barrels, I've found that these measurements are merely "splitting hairs" and are pretty much a complete waste of my time.
Now I just size to ".452 and I'm happy. Interestingly, Lyman suggests sizing to ".451. It would appear that some engineer mixed Prozac with his micrometer, but hey, even ".451 works fine with soft lead. I used to use the H&G #68 type bullet also, but I've switched over to the Lyman 452460 type because it's design has the promise of a very slight accuracy gain over the #68 without going to a full SWC. It does require twice the amount of bullet lube, but with about 20lbs of beeswax sitting over here, I've got no reason to care about that.
Anyway, at 850fps with a soft lead 200g bullet, there is always enough obturation. New casters frequently confuse the effects of high velocity rifle shooting with low velocity pistol shooting, but there is quite a difference. With rifle shooting, there are many more considerations when casting. With slow velocity 1911s: Keep the lead soft (ex: unhardened wheel weight lead) and size to ".452.
I'd venture to say that cleaning your barrel with a bronze brush a few hundred strokes would yield the exact same benefits as the "moderate wear" effect you are thinking about without actually wearing the barrel.
Keeping a 1911 barrel clean will help you out some. I used to use the "dirty powders" with my extra dirty bullet lube. I could definitely notice my groups open up after a few hundred rounds. I still use my "extra dirty" bullet lube (50/50 alox and beeswax) but I've switched to a much cleaner powder these days. Before I switched, I'd just run a bore snake through the barrel between courses of fire. I love that bore snake!
Having a smooth, consistent bore is a good thing. Wearing down the rifling is not a good thing. When people start shooting moly coated bullets through a 1911, I will be done with the Internet. :grin: :grin: :grin: :grin: :grin: :grin: :grin: