Yes, I know. You should be asking the guys that use it that way. Sometimes they have a big cam that has a very low vacuum at idle, and they use it this way. Ask them.
Big cam, inconsistent vacuum, the very reason not to run full vacuum advance at idle.
Initial timing is crucial when tuning a carburetor during idle and transition.
Again, what happens when you mash the pedal, all the vacuum advance, say 10 degs goes a away.
