Im 5'10", not sure of my reach. My guns that have wooden stocks have all been customized to fit me which is cutting a bit off, not sure how much..My berettas have been customized as well.. All that seems to help with wing shooting more than turkey hunting. Shorter guns..barrels/stocks IMO seem to be more comfortable holding on my knee when im waiting for the turkey to make that last commit into the call. Less weight out on the front of the gun and a shorter stock makes holding the gun up and manuvering the gun from a sitting position much easier. I have a gun that was cut to fit me when i was 12..21" bbl/ short stock and it is the easiest gun to turkey hunt with I own.
I would assume he is talking about the adjustable stocks that you see on here. They do actually make the guns look short and like military issue..cool as the other side of the pillow. I have a son being born next week and im already thinking about rigging a gun with an adjustable stock for him.
P.S. The first time i saw one of those adjustable stocks on a turkey gun a friend of mine's grandson had one and as it started breaking daylight i looked over and thought to myself "that boy must be serious..hes got a dang riot gun in his hand"