I think I understand what you are suggesting, where I lack the talent is understanding 30 degrees versus 1 degree. Assuming advance would put the rotor slightly before the #1 location on the cap?
There are several good youtube videos, one from MSD that shows how to check your rotor phasing. While running the motor at higher rpm's ( when advance is all in), you shine a timing light at the distributor cap to see where the rotor is in relation to the tower, at that 30 degrees. hence the hole in the cap.