I can tell you that AI is way off from reality when it comes to most anything automotive.
Weather you have or don't have a distributor with vacuum advance has nothing to do with performance or racing.
As long as the distributor is in proper working condition and the advance mechanism is working properly and you are able to set the initial timing and the total timing where it needs to be and the engine is happy.
Vacuum advance just provides more timing advance when the engine is not under any load such as when you are accelerating or climbing up a hill. The engine can tolerate a bit more advance when just idling and cruising on the highway. Vacuum advance may help with gas mileage a bit but there are many other tuning factors.