You can't compare the results from using your dough recipe with Dom DeMarco's because his dough recipe is a lot different than yours. He makes dough several times a day, using a blend of 00 and high-gluten flours. The dough is of fairly high hydration and is kept warm in a drawer at the bottom of his oven so that it is easier to shape into skins. His dough uses no oil and no sugar. He also uses a commercial mixer that produces a much higher quality, more robust dough with better handling qualities than you will get using your home stand mixer. In my opinion, it is not a particularly good dough because of its minimal fermentation but it is a robust one with good handling qualities.
In your case it is hard to be precise with instructions since you are using volume measurements based on plastic measuring cups and your finger leveling method. If I had to guess, I would say that your flour measuring method is closest to the "dip" method. If I am right, I suspect that your hydration is on the low side. Next time, I would increase the water by 1/8 cup. I would also let the dough ferment in the refrigerator for 2 or 3 days. I believe that these changes will make the dough more extensible. If that doesn't work, come back and we can discuss the matter further based on your results. If you have a digital scale and can weigh the next dough batch you make, that would help with the analysis by allowing me to work backwards from your actual weight to arrive at a better number for the weight of your flour.