This is how I've always understood it.
Few pitchers will generate much of their available pitching power when they pitch without their windup, while DGers can achieve long distances while they throw standing still.
The mechanics are totally different. Pitchers must generate tons of speed with their arm strength (and the further you keep the ball away from your body, the faster it travels as you bring your arm around), while DGers are all about late acceleration and the hit, in order to get the disc spinning fast enough for the discs natural flight characteristics to affect the flight.
So long as the disc is spinning fast enough, it will fly far. Usually we are most effective distance-wise when we are throwing 75-85% power with great snap, and failing when we "strong arm it". Where as, a change-up, often ends up in the dirt.
That's ok, though, as the whole point of pitching is to keep it from being hit well, not flying well itself...
It's just apples and oranges anyway you look at it, imo. My bro is a baseball guru (ump, coach, longtime player) and he always says that he had to unlearn everything he was taught about baseball in order to DG well, because it is the complete opposite of baseball.
i.e. baseball elbow out, DG elbow in.