Yes he is, because Rory has the physical ability to spin his hips faster than nearly any other tour player. That is why he can hit the golf ball further even though he's loosing 8 inches on his radius of his golf swing. That is his physical attribute. There is no doubt being taller is an advantage, majority of the top ten long drivers are tall, specifically the top 5.
If you want to get into the match
v = w*r
That means for Rory to have the same velocity of the clubhead as the other long hitters on tour, who are way taller than him, he has to make up the radius difference in rotational speed. This is special to him because no other 5'9" guy hits as far as he does on tour.
right, I suppose that wasn't the best example, sergio's a bit better, he's not very big but creates tremendous lag and hits the ball as far as the long hitters with a shorter driver...I've seen plenty of big guys that don't hit it long and plenty of small that hit it far is my point. I don't think body type or size are the only factor, yes being tall helps tho.