that's not how cooling works. water doesn't work like that it will always be picking up and shedding heat through the radiator. you can either circulate it slowly so the water stays longer, which can cause centralized boiling which will create hotspots, or you can make it pass through the radiator more times in the same amount of time, which is what using a bigger water pump does. it's just an old tale like cars liking exhaust backpressure.
