I agree with this view. Oswald could not hit water if he fell out of a boat.
And you have sources better at judging rifle marksmanship than the US Marines?
(200 yards seated rapid : 9 out of 10 into the central area of a head and shouders target.)
I have fired both weapons. The M1 garand is an excellent firearm. At 200 yds, in a prone position, I put 8 out of ten in the black the first time I ever fired a garand. The carcano was a piece of shit. Even using the scope that it came with and adjusting it several times , the performance was no where near as good as the garand without a scope. They are not the same weapon.