Manifold Vacuum Advance what am I not getting?

10 Hg @ 24°
15 Hg @ 42°
1300rpm in P and 850 in gear
That doesn't answer a thing. I asked if it ran good without the higher advance. This tells me nothing. The point YOU'RE missing is that I am an advocate of MVA. Lemmie tell you something. I've been working on and tuning on cars since 1974, I promise you "I" am not missing the point.