I wondered about the same thing until I saw a high speed film of the archer's paradox. The theory behind the myth is that you want your arrow to spin away from the riser... fact is, the fletching doesn't bite enough air to start spinning the arrow until it's 3-5ft from your bow. I have shot arrows with both a left and a right helical and the helical made absolutely no difference at all. The arrows were shot into the same target,each shot alternating lt and rt helical for a total of 5 arrows each and all grouped togather.