I find the world of woodie spines to be not so exacting, if not downright uniquely specific, sometimes even within a "matched" set. There are Many factors to consider, and it all starts with the bow, where the arrow plate resides with respect to the center of the limbs, and the archer. One could write a book about woodies, and the final sentence would be, "Select a single batch of shafts with as much knowledge as possible, and then test, Test, TEST."
Again, the one clear and present condition will be the location of the arrow plate.