Very true, proportioning is key, you want as much rear brake as you can get, but not too much, as the rears will lock up before the fronts reach maximum stopping power. These thrsholds will never be even approached in a street car, as varrying traction conditions, could produce a rear lock up too early, and could assist with the tail coming to the front (ABS would help though)
The front brakes do 70 to 80% of the braking. Often times a big brake front upgrade kit feels great when they grab hard and fast. But if you do an annalysis of a cars actual stopping distance, the backs must be properly matched and proportioned to the fronts for high performance stopping.
The back brakes are important also, not just the fronts.