Also, you can shoot vanes off your hand. I do.
I have some 30 inch carbon fiber arrows I got for christmas, and they have vanes. I wear the vanes out, yes.... but it takes a long time.
when the vanes wear out, I replace them with craft-store feathers...
I have found no difference between 2 fletch and 3 fletch arrows, except 2 fletch is much cheaper and easier. you can get up to 2 arrows per feather.