I used three burners on HI and positioned the MPO almost all the way to the left (so the left side of the MPO was over burner 1 and the right side was over burner 3). I did not use burner 4. Heated the top stone for about 20 minutes, then added the bottom stone for at least 15 minutes before baking. I think I left the chimney open just a slit the whole time. (I think I kinda understand what the chimney does, but I'd love some help understanding how the chimney affects everything.)
15.75" bottom stone with foil hugging the bottom and sides of the stone. Top stone was on MPO shelf #2. I think the top stone was positioned at the back of the MPO, with a 1" gap between the front of the MPO and the front of the stone.
I believe both stones were 550 or a little hotter when I baked the first pizza. I did not check temps for the second pizza.
The burned areas seemed to occur at the very back of the grill. It was a small area, but it happened to a significant portion of the pizza(s) because I rotated the pizzas. I may have positioned the pizzas so they were hanging over the back edge of the stone, but I'm not sure because I can't lift the front of the MPO high enough to give me a clear look at the very back of the pizza and stone.
This dough used the same formula I listed early in the thread, except I decreased the hydration 1%. Refrigerated around 48 hours, then pulled 3 hours prior to baking.
100% Superlative flour
Each skin used 13.5 oz of dough, rather than 13 oz, which I had been using. I increased the dough ball weight to account for a little more rim than I had been getting. Good change. I'm gonna decrease the ADY to 0.25% with the next batch.
That weird-looking spot on the cheese pizza (back right) has a somewhat interesting story. When I was peeling the skin onto the stone, I screwed up and got too much of the skin off the peel near the middle of the stone (rather than the back of the stone). So much of the skin was off the peel that I couldn't push the skin back without mangling the pizza, but I also couldn't pull the peel out from under the skin because half of the pizza would have ended up hanging off the front of the stone. So I kinda geeked out for a moment and tried to figure out how I might be able to save it. I remained calm enough not to do anything stupid, and after probably ten or twenty seconds I realized that the part of the skin that was on the stone had probably already baked enough that I could go ahead and push it all the way back, then peel the rest of the skin. It worked.
Like I said, these pizzas were awesome. My uncle and his ladyfriend agreed.