A Feather in an Oval V-Groove is a Fringe of material left behind where the cut started and ended on either the inside/outside cut of the Oval V-Groove.
If the Outside cut of the Oval V-Groove has a Feather, Increase the Outside Oval Rotation.
If the Inside cut of the Oval V-Groove has a Feather, Decrease the Inside Oval Rotation.