When initially profiling the back of the limbs, I leave the tips a little wide. I cut rough string nocks in and string her up. I normally like to see about 8-10# heavy at this stage. I will mark the stiff limb as bottom, unstring her, and then add my overlays. I want to make sure that I didn't miss weight too far off to recover before continuing.
After the tip overlays are done, I narrow the tips closer to final width. This will remove most of the initial string grooves. I use the shadow of the original as a guide for the final grooves.