I add roughed out overlays with a stringing groove before I start tillering, this way I can easily string a high poundage bow. I only cut a string groove across the back at this point
When I get to full brace I use the string to locate the perfect angle for the side grooves before I cut them.
I finish shaping the nocks when I know the bow is going to survive, I leave the stringing groove which I have found to be very handy.