If I had to describe the overall difference between my normal grilled pie and this one, I would say this one was mostly chew, a little crunch and almost no char. My family clearly prefers to have more of a balanced blend of chew, crunch, and char. Apparently that only happens, for us anyway, at 800 degrees or so. Crust, cheese, sauce, and spices just taste better to us at higher bake temperatures than lower.
I have learned something else from this experiment though. A shortened preheat time equals uneven cooking. From the pictures you can see the top cooked faster than the bottom. Apparently the temperature of the air was higher than the tiles. So it's the tiles that take a longer time to heat up than the air. Interesting. Now here's the twist which makes this so maddening for me. When I used a pizza stone in place of the grate & tile configuration I have now, the results were the exact opposite. A short preheat would equal a charred bottom and a raw top. Those sorts of huge swings in possible outcomes are enough to drive a guy to drink and kept me up at nights.
A 30 minute preheat with a double stack of tiles on the grill grate seems to mostly balance the air and tile temperature out. Looking back on recent pies, I can deduce that the air temperature is slightly higher than the tile temperature which is exactly where it should be as the top needs slightly more heat than the bottom due to sauce and toppings.
Dave, you make a great point though. It did remind me of a NY "Street" pie as well now that you mention it. It just wasn't close to a coal or wood burning oven look. It had a Bakers Pride or Bari oven look to it.
Snowdy, have you implemented the calibration mode for your home oven to get an extra 35 degrees or so of heat? The adjustment might get you closer to char...