That is not what your post were saying so.....the confusion of your post. The Master training lectures are on the web so any one can look them up. Once the throttle blade is opened the ported position to the distributor is activated and the vacuum at that port is almost the same as the manifold vacuum off the intake, or the PCV port at the back of the carburetor. Basically an on off switch to prevent any vacuum advance from being applied at idle with throttles closed and high engine vacuum.

So as stated Chrysler used the ported (Vacuum Spark Port) on the carburetor for the distributor vacuum advance. The vacuum advance was used to adjust timing to account for the motor load, while the mechanical advance account for the speed of the motor. Carters only had one vacuum port sized for the distributor.
Holley's did have more on the throttle plate, but as far as the time frame discussed predominantly Carter AFB and AVS for the 4 barrel cars as explained above.