I' ve been experimenting with fletching vanes in different ways. I' ve tried them at different angles on the same arrow (not all 120 degrees apart) and with different degrees of offset. So far, all the arrows appear to fly the same. I also commonly practice with an arrow that has only two vanes, and I can' t see any significant difference. As long as the fletching isn' t bouncing off of something, I don' t think there will be a huge difference in flight. I will mention that I' m doing this out of a well tuned bow, that will put a bare shaft very close to my regular arrows. If it was way out of tune, the results may have been much different.