I have never experimented with it, because I didn't need too with the hardwoods i use. The theory has been that the plains Indians only have Willow and other soft woods to use for arrows. They grooved the arrows and when heading over the fire and straightening it kind of heat set, tempered, or something the wood helping it stay straight. That is what has been theorized. I have thought about trying it on the hazel arrows I have left, but I never make a grooving tool. They get bent in humid weather and need hand straightening after ever shot, but do better in the winter when its dry.
That said, when I went to the Smithsonian and looked at arrows I didn't see any with grooves from the plains, so I am not sure many did it. Most were 21" to 23" and 9/32" to 7/16" clean and very even except for the bulb nocks. I lost all my pictures and notes in a lightning strike with fried my server and destroyed all hard drives.
