Smoking my pork butt got outta hand

[cdcox]

I have been thinking about Inmen58's fire. I have melted aluminum (melts at 1221 F) cans in many a camp fire. I have no question that even through two metal cookie sheets, a chimney full of coals could bring the surface of the wood up to 500 F which is hot enough for it to ignite. The pan in contact with the wood is pretty flat and would make good contact with the wood; it is also an excellent conductor of heat. I'm sure every one who has watched a campfire has seen a piece of wood not in the flames get very hot until it burst in to flames without ever coming in contact with flames from the main fire. Same thing could happen here.

The part I am struggling with is the supposed gap it time between when the coals were removed and the fire started. It would seem that 2 hour is enough time for the heat to dissipate. I'm wondering if the wood actually started burning when the coals were in the chimney, but the flat bottom pan prevented much oxygen from reaching it. The oxygen starved fire just kind of turned the wood under the pan to charcoal, generating enough heat to keep the fire going at a low level. It finally burnt to the point to open an oxygen pathway at which point it burnt into flames? Just hypothesis forming at this junction. Really interesting.