Oswald was rated as a little better than average by the marines which made him an excellent shot as against the usual sport hunter.
It's a puzzle to me why some folks keep referring to Lee's Marine Corps shooting ability..... It's totally irrelevant.
Lee was trained to use The M-1 Garand with adjustable peep & blade sight, which is totally different than the fixed V notch / blade sight of a model 91/38 carcano.
Some ignorant folks think that simply because a man is a good shot with one particular rifle that he's equally good with some other rifle...... They are simply exposing their ignorance.
A smooth, consistent trigger pull is the single most important factor in good marksmanship, and the hardest to master. Learning the correct sight picture only takes seconds; a proper trigger pull takes considerably longer.