Hank,
MVA is no more of a useful 'crutch' than ceramic coating your headers, using a phenolic spacer under the carb or making sure your brakes are not dragging. They all provide a benefit that was not there before.....
I will happily capitulate. You clearly have more knowledge on the subject than I do.
But this is the case in which I personally have used manifold vacuum for the advance as a benefit.
On the dirt track cars I played with the "wisdom" was to lock the distributor solid.
Personally I thought this was dumb and left power and throttle response on the table but I was young and the old heads weren't listening to a punk fresh out of trade school.
So they stayed locked.