Base timing. Really ?

ok, so when we were talking about the FBO plate working against me, is it because the vacuum advance can get the advance as high as it needs to be under light throttle with the plate? Im assuming thats why being the full advance under WOT is normally around 34-38 with a decent cam nd all..or am i totally wrong..? In other words, the FBO plate is not hurting anything UNLESS using the vacuum advance? AND, if using the vacuum advance, you would want a spring tight enough to keep it from passing 34-38 total under WOT?