Ive always used 3, 5 inch shield cut feathers on my arrows...left helical. I am a big 2 blade fan and like to shoot the stos, zwickey and simmons....as they fly great for me. As of late, Ive been wanting to try some 4 fletch...just got the nock receivers (4@90) for my JoJan. My question is this: using 4 fletchings instead of 3, can I get away with using a bit shorter fletch? Say 4, 4inchers? Or should I stick with the 5 inch? To make it more interesting, Im thinking of trying parabolic! So using 4 fletch, what would be a better formula: 4, 4 inch shields, 4, 4inch parabolic or 4, 5 inch parabolic? What do ya think?