Some fine tuning of dynamic arrow spine can be done by changing the brace height of the bow. If your bare shaft is showing slightly stiff, you can try adding twists to raise the brace height. Make sure you stay within the bowyer's recommended brace height ranges. I believe you will find that the effect of brace height on dynamic arrow spine is minimal. This should only be done after getting the spine as close as possible by adjusting point weight, shaft length, or trying a different shaft. Subtle adjustments to dynamic spine can also be made by using different, or no, string silencers, and adjusting the location of the string silencers on the string.