Okay, I'm going to do basic math here.
We all agree WHM > Diurnal and SCH > Nocturnal, so that means:
2x SCH > SCH + AST
2x WHM > WHM + AST.

Now you are asking for test, but what you don't seem to realize is that this was tested back in 2.0 already. Just ask any Scholar how much fun it was to heal Titan HM with another Scholar. Heck, Turn 13 would be impossible to do without a Scholar, and taking an AST instead of a WHM would make the fight way more difficult.