I look at it this way- Without fairly good bare shaft flight, you are only getting good arrow flight because your feathers are steering in a big way. Then add a broadhead to the mix, and what might be ok arrow flight with a field point becomes difficult. With decent bare shaft flight, your feathers don't need to do a lot. I missed a nice elk this fall because of poor arrow flight, which I attribute to not enough practice with broadheads (most were flying pretty good). When I bare shaft tested things were bad. Once I added 75 grains upfront both the bare shaft and broadhead (on fletched arrows) flight improved a lot.