About the bake time. Their bake times seem to vary quite a bit. I have read of bake times from 4 minutes on up. When I was there with you, I ask the man making pizza (not sure if it was Bruce or someone else) about their bake times and he said 7 minutes. I have been pondering that 7 minutes for awhile now, and I am concluding that the bake time averages around 5 minutes with a min and a half to 2 minutes on the reheat to equal 7 minutes. But I also understand that they don't always reheat whole pies as John C. and Frank have told me. So a straight 6-7minute bake isn't really out of the question.
Now I know you love a 4 minute bake, but when we talk of bake times, we have to take lots of other factors into consideration. Namely the type of flour, hydration, use of oil, and how the dough is made. Believe it or not that all affects bake times. A 4 minute bake time using 2 different doughs will yield 2 distinctly different crusts.
For my specific dough, I did a bake Saturday night at 700F + in the 3-4 minute realm and I wasn't happy with the crust even though it browned up nicely. It was too soft for me. Of course today's bake wasn't with the exact same dough either since I had already made some adjustments to the formula. For tonight's bake I was really shooting for a 5-6 minute bake with and without a 1 minute reheat.
So for this dough formulation, it really seem to benefit from a 5-6 minute bake, thus the 600F-ish temps. I think PT is baking around 650F-ish right?
The guy making pizza when we went was Bruce. If he really said '7 minutes' for the bake time, then that might very well be one additional reason why I prefer Michelle's pies so much more. It didn't taste like a 7 minute pie, but the crumb was a bit drier than usual, so perhaps Bruce is extending the clock. That all being said, while I've never timed a pie, out of the handful of people that have, I've never heard anyone give a number higher than 4:00.
Also, I've never seen Pizzatown re-heat a whole pie, even late at night when no one's there. In fact, I've never seen any NY area pizzeria ever reheat a whole pie- unless someone comes in and asks for 8 slices. Pizzatown is too busy to have pies sitting around.
I'm a little flexible when it comes to bake times

If you, for the sake of a little extra crispiness, want to do a 5 minute bake, I'm not one to judge. 6 raises the hair on my neck, but 7- you start doing 7 minute NY style bakes and you and I are no longer friends

Btw, if you really want an undercrust that cracks when you fold it, you can achieve it quite easily with a 4 minute bake + re-heat, as long as you let the crust cool long enough between the bake and the re-heat.
I'm not sure if that is refractory FB or just plain FB in my wfo. If I had to guest, it is probably refractory FB. They come in 24x24" slabs and are almost 2" thick IIRC. I'll have to look it up to be sure.
Sorry, I've been spending too much time on Forno Bravo. I used FB as an abbreviation for Forno Bravo, not firebrick. 610 with firebrick might be in the 5-6 minute realm, so maybe the Forno Bravo refractory isn't that different from firebrick after all.
Boy if Pizza Town is an 8.5 out of 10 for Scott, I'd love to see what 10 really is all about.
I'm being a bit arbitrary here, but I would split NY style into two sub styles- crispy and soft/puffy. There might be a magic point between crispy and soft that encapsulates the best of both worlds, but, for now, I think it's easier to split it. You've done 10 out of 10 crispy pies- at least 10 out of 10 for me. An undercrust that cracks, for me, is a defect. But the first video you did in the string of videos, when you squeezed the rim and it sang- that pie was definitely a 10 out of 10 crispy NY style pie. I can pretty much do a 10 out of 10 soft/puffy pie on command, especially with the flour I'm using now- Spring King. My undercrust coloring is very similar to yours, but the texture is pretty floppy and my rim is soft, puffy and wonderfully chewy.
Btw, you'll probably be pleased to know that I'm now doing re-balls

It took me a long time to tweak my process to get the re-ball to work (the balls weren't sealing), but once I got it working, the difference was substantial.
Edit: Fixed typo