Pumping ABS during normal driving; yes or no?

My car has ABS. I know I'm not supposed to pump the brakes during an emergency situation when the ABS is activated. But what about driving normally? What about when I'm going down a long steep hill and slowing for a stop sign at the bottom of the hill? Do I have to ride the brakes and wear them down constantly the entire way down the hill, or is it ok to lightly pump the brakes as I slow down and without the ABS activating? My father and I are swabbling about this. He thinks the ABS constantly work any time you apply the brakes and is always on. He think braking under normal conditions in a car with ABS is different than braking under normal conditions in a car without them. He thinks pumping the brakes at ANY time while driving the car will ruin the ABS. Please let me know which of us is right!