Vacuum advance issue

D. Vizard claims he uses vac adv [ manifold connected ] on his circle track race car.
There is no reason not to use it if the engine specs/conditions suit it.
Yes, some use it, but it usually is not used if your foot is to the ground. Drag racing doesn't use it. Vizard uses it with manifold vacuum, not ported vacuum, so there is a different there also.