The oiled pan is a favorite of mine. My favorite pizzeria in Pisa (Il Montino) uses this approach in combination with a wood-fired stove. The result is a pizza that causes a bit of controversy, as its crust is almost fried, but for me, it's damn tasty.
The rock ain't a gadget -- it's how breadbaking should be done. Basic physics -- stick a pizza pan in the oven on a rack, and you have a round object floating in air, often on a nice metal conductor that spans the temperature of the raw dough and hot oven. Air is a good insulator. So the gradient between the center of the dough and the outside is shallow, resulting in a "spongy" pizza. If the pan doesn't have holes in the bottom, the bottom is actually softer than the rest, because moisture gets trapped. Then, when you slap toppings on it, the top of the pizza dough is raw -- since it cooks last.
But, you put a rock in there, and its porosity prevents the moisture from accumulating. And when the rock is hot, it stays hot, and cooks that pizza straight.
Now, for deep dish, I'd use an oiled pan on a rock, but at a lower core temperature (Say 400 degrees). Use a sponge the night before, high gluten flour, and get that yeast really going.
