Some time ago I bought a dozen new carbon shafts and I proceeded to fletch one up and got it cut and weighted for perfect flight, then did up five more just the same. All but one gave perfect flight; I worked with the problem arrow, tried every imaginable solution; all to no avail. The arrow usually hit close to target but it always did some super funky dance moves in flight and often hit at an angle. I finally gave up and assumed it must be a defect in the shaft that I could not see. The other day it hit me that there was one thing I had not tried; I re fletched it and BAM perfect flight. I had bought a bulk bag of 100 right wing fletches and apparently a lefty got into the mix and I did not catch it when I first fletched the shaft. Rights and lefts REALLY DONT MIX!