ok, bro science was being a bit hyperbolic.
I now see its about enduro and i was looking at it from an XCO / XCM point of view.
Stil though:
Braking force distribution myth – how do you really brake?
You should use both brakes, period. The most power is in the front brake. You can lean back as much as you want on a descent, the rear brake alone will not slow you down enough. But i understand from an enduro perspective, you you use the rear brake a lot in a dragging fashion to modulate speed, so yes, bigger is a good idea.