And it does further my argument, which is to reject your claim that fires only affect structural integrity if the heat is very intense and long lasting. I am telling you that exposure to sufficient heat for a duration of half an hour would be enough to affect the structural integrity.

There is no evidence of fires reaching temperatures hot enough to weaken steel, let alone melt it (even though molten steel and concrete was found), on 9/11. Except for 3 isolated spots NIST, who researched the events for the government, didn't find that temperatures exceeded 250C (page 140). Also take a look at these FLIR images.

The 3-5x number, while correct, doesn't address the failure mode here. Yea, you could put the 3-5x the weight on top of those columns and they might survive, but that's not what caused the thing to collapse. The heat from the fire caused the structure to deform and stress to the point where the top floors fell down on top of the remainder of the bottom, severing the weak links along the way until eventually the force of the falling structure applies more than 3-5x the designed load.

You fail to provide any evidence of any fires reaching a hot enough temperature to deform and weaken the entire structure in order for it to collapse - let alone so symmetrically, so entirely and so fast.

You're not really looking at the problem correctly here. You don't need to "destroy" each floor to cause it to fall. Instead, let's imagine I nailed a bunch of boards between two posts, such that the nails were just enough to hold each board up. If I cause the top board to fall onto the next one, I don't need to destroy the next board to cause it to fall, I just need to exceed the capacity of the nails.

You're not really looking at the problem correctly here. Let's say a floor falls onto another one. For some unknown reason it falls onto the other one in its entirety at the same time. The floor it falls onto it welded and bolted to the core and perimeter columns. The lower floor is going to provide resistance to the falling floor. Some of the energy in this collapse is going to be transformed into physical deformation, so now you have less energy than what you started with. Repeat for a few times, and all the energy has been dissipated. Even if the floors could fall at free fall speed, you cannot explain what happened to the core columns or the perimeter columns. These structures were way stronger than floors so if the floors simply come lose of their hinges and fall, nothing major will happen to these columns. Zero, nada, zilch. The floors cannot pull the columns down with them, that's not how it works.