This could be true, but is not a proof because it assumes the collapse was natural with the first confirming the second and second confirming the first. There are many reasons to reject CD but this is not one of them.
Did you find evidence for CD? I was not talking about CD, I was talking collapse progression was confirmed, twice, and math can be used to check it.
Natural, fire is not natural on 911, it was on purpose, a crime. It does not matter what started the collapse, "natural" or CD limited to the impact areas, the collapse will not arrest, it will do what was seen by two full scale models. The collapse progress is no surprise based on the structure of the WTC, something Robertson knew immediately; for most would take some study of the WTC structure. I had no problem on 911 understanding it was fire based on observation of events (including the planes being commercial), and gained a better understanding when I studied how the WTC was built. I have no doubts fire can start a collapse, steel fails quickly in fire, and CD proves only a tiny amount of energy is required to start a global collapse, and gravity does the work of demotion.
How do we model the fires or explosives. Fires are a most inefficient way to destroy buildings, it took office fires with the heat energy of 2,700 tons of TNT to start the collapse in the towers. The gravity collapse which destroyed the WTC complex was only 137 tons of TNT for each tower, potential energy released. CD is not done with fire, it is inefficient. The WTC towers could be destroyed with small amounts of explosives, from similar locations for a top down failure, using the mass/gravity to do the rest.
Combined with the fact there were no explosives, termite or other devices used on 911, and complete lack of evidence for the same, it is proof collapse continues, as seen. What we saw is proof of the collapse not stopping after starting.
Full scale models are better than scale models to demonstrate collapse progression.
For 911 truth, no scale model would be enough to keep them from promoting the "official narrative" is like a fairy tale, not a factual account, or spreading the "official" investigation is effectively a disgraceful cover up, and saying little was revealed and much was concealed. For these tag lines, which might sound great to 911 truth follower, models or investigation may not be enough to break their illusion of an inside job or CD. I suspect most 911 truth claim believers quickly figure out claims from 911 truth are baseless, and they join reality.
It is tough to model the collapse progression at a level for doubters. Unable to grasp a floors fails at a certain mass, and no knowledge the WTC is a system depending on floor to core to shell integrity, how do you do it?
Scaling gravity, connection strength, mass, etc. It would be hard to make a model to model the collapse, much more easy to make a model to model the structure appearance for a wind tunnel test...
I like all the model I have seen, the really bad wire models, or my favorite the in box plastic tray models, cold you imagine 10 foot thick plastic ceilings, and walls? Now that is a model.
I like the washer model; when it models a floor can hold a set mass, all the way down; the collapse would progress, accelerating, and the speed would reflect the momentum transfer of the collisions. This can be done mathematically for the WTC, and it matches the collapse speed profile.
How can a collapse with more mass than a floor can hold, be arrested by the floors which can't hold the mass? Even if we magically stop the collapse at each floor, then hit the "play" button, the floor fails.
Who can't reject Judy Woods pool ball model at face value.
NIST did full scale models of the WTC floor sections to test. And full scale sections of offices. These test confirmed WTC was up to specifications.