Think of the physics required to impart spin into an arrow.

The closer to the centerline of the shaft you attempt to generate rotation, the more energy is required to accomplish the rotation. It is more like a lever, the longer the lever given the same fulcrum to load ratio, the longer lever is able to place much more energy into the load.

The more offset or helical placement of your feathers or vanes, the greater leverage effect on the arrow shaft. Since the vanes are at the greatest distance from the center of the arrow shaft, they have the most to offer in the form of rotational energy. The increased suface area of the vanes(feathers) cannot be duplicated (force vs force)by any other arrowcomponent and therefore they are the most effective in producing arrow spin. This is because the fletching is in constant contact with air. This interaction is what produces the energy that we are talking about. It occurs the entire time an arrow is in flight.

Alas, the QuickSpins. They use this same principle of physics, but I have never used them. Ican control myshafts with helical or extreme offset fletching w/a drop away rest. No clearance issues and without the added weight of theNAP vanes.

And yes, all concessions have concequences. More spin = less speed. But what are we trying to achieve here, better accuracy at a slightly slower fps or just acceptable accuracy at blazing speeds?