Power Valve Selection: The Definitive Answer
Yep, the holley recommended method is not a good one for the correct PV for the car.
AF meters are the best way along with a vacuum gauge while cruising is the best method. Roll into the throttle and note the afr spike and vac reading. Rarely is that close to the methods that have been used for years.
A properly set up carb will not care if the PV is open at idle. The carb is nowhere near that circuit through the boosters. The PV adds additional fuel to the main well, no place for it to go once there.