You are both correct sirs...8)..one other option is to remove the vacuum advance diaphram and get someone to re-curve your distributor...they can set your total timing and let you know where to set your intial timing...
Even with a re-curved centrifgual advance that gives maximum power at WOT most street driven cars will benefit from a properly set up vacuum advance because at part throttle (light load) when the vacuum advance comes in more total timing can be used which helps fuel mileage and keep plugs cleaner.
Here's an example of mine. Initial timing is set to 18 before and add in the centrifugal advance of 16 degrees the total timing is 34 degrees all in by 2500 rpm. If I go much more than that it will spark knock at WOT. The vacuum advance comes in at part throttle with an additional 17 degrees of timing so that puts the total at 51 degrees. If you notice I said earlier it will spark knock if I go much more than 34 degrees total timing yet I can run 51 degrees due to the vacuum advance without any spark knock. The reason is it's at a part throttle light load. At full throttle it would spark knock like crazy. Running the vacuum advance raised my fuel mileage approx. 3 mpg. and the plugs stay cleaner.
