He didn't address one of the most important aspects of pizza making, though: the heat source itself!
Other pizzas use a variety of heat sources, but Neapolitan pizza is baked at between 750 and 1,000 degrees in wood-burning ovens. I can't imagine even an improperly-packed pepperoni wouldn't curl a bit under 800+ degrees of real flame. Of course the stuffing causes density changes, but at a certain point the surface tension/temperature differential will simply have to cause some curling. Next time i'm at my friend's house for a bonfire i'll toss a couple different forms of pepperoni in to test this.