When I tiller a bow, I've always just centered the bow on the tree, but when doing some reading I noticed that some people shift the bow in one direction, I assume to put the arrow shelf in the center of the tree. Perhaps this is done on a bow with a shorter bottom limb where the shelf actually falls closer to center. That part I'm not sure of.
Anyway, on a bow with equal length limbs, should I be shifting the bow to the side and centering the arrow shelf on the tree, or is the way I've been doing it ok?