This is kind of nit picking technicality, but hey, that's life.
Yes the old guys can sit in one place and shoot the crap out of what comes in range, but if you're in Boston, and the fighting is in NY that isn't much use.
Remember, the really effective forces in history, Stonewall Jackson's "foot Calvary", the Roman Legions, Bedford Forrest' s confederates,even the British Corps of Guides in India, all owed their reputations to their ability to cover ground faster than the enemy could react.
Troops that arrived in Gettysburg on 4/7/1863 didn't get famous.