I think it is more a case of "shooting a lot" and hence getting a "feel"

In my opinion, the bloke who shoots a lot with open sights will still hit more game per shot fired even when he is nearing blindness. And range will not be a limitation.

For those who might read this thread who have fucked about with cars...they will know that when they let the clutch out between the gear change and give the engine the right revs it all works better than the synchromesh. And you don't need a rev counter to do it. Feeelllll

Mike