RE: bare shaft tuning
I don't agree with that last statement at all. I don't feel paper tuning tells you much of anything and is only the starting point of tuning, certianly not the end. I know quite a few that don't even bother with it, including myself.
I agree though, when I bare shaft tune I do not concern myself with how the arrow flies or how it looks in the target after it hits. I am only concerned with where it hits in relationship to my fletched arrows and how it groups. If you feel you could do better with the centershot, then by all means work on touching it up. If changing your rest has no impact then it may be spine. Try taking a turn out of each limb or adding a turn and see what happens. This will change the spine of your arrow.
Another good thing to do is to shoot at a vertical and horizontal line for groups. Adjust the rest or poundage until they are as close as you can get them to the line. When shooting for centershot shoot the line that runs from the top to bottom of your target and only concern yourself with how the arrows hit from left and right. And when adjusting the nock point do the same thing with the line that runs from left to right. Only concern yourself with how they hit up and down. This is how you fine tune your rest usually. It takes some time and dinking around.
Remember with a release there is no set rules. Usually the obvious adjustment works, but not always. You just have to tinker around until you get the results you want. And go in small increments. Sometimes if you go too far it will do the same thing again.
And remember, you can't tune better than you can shoot. If you have trouble grouping fletched arrows together don't expect things to get any better with unfletched ones. They are more sensitive to rest adjustment, grip, torque and form.
When I bare shaft tune I don't use a competely unfletched arrow. I take some fletched arrows and cut the fin off the fletchings leaving the base and glue. This helps the arrow retain it's original weight. Taking weight off the back of the arrow will effect its FOC and dynamic spine. This effects how it flies.
Good luck,
Paul