How's it going to work against coriolis. If shooting south to north you're looking at a target that is moving to the right. If you're shooting north to south you're looking at a target that is moving to the left. West to east, target is moving away, east to west, target moving closer. I don't even figure it in shooting a mile, I think the wind is a bigger factor to be concerned with.
Spin drift? One time has it ever come into play for me. Zero wind, 178 gr out of a .308, 800, 900, 1000 yards, watched the bullet drift right of the target at 800, with a solid zero and not a leaf flickering. Rare conditions.
Just my opinion.
I did hear a tale of a LH twist barrel that was RH threaded into the action. The barrel unscrewed itself from the action. Not totally, but did daylight barrel to action.