I mix the flour and the (tepid) water and let it proof before adding it to the other ingredients. It should rise to a noticably larger volume after a couple hours. Another trick, I set the dough in the oven with the oven light on, that provides just a little heat to help the yeast along.
I only kneed enough to mix the ingredients well together. Also, be sure to add oil to the pan. Seems to really make a difference in the resulting texture, even though not really needed to prevent the dough from sticking.
That being said, a Giordano's crust does not 'plump' much. Most of the final pizza thickness is the 'stuff', not the crusts.