In both the WTC Towers, the ruptures and crumblings initiated from the zones and floors where the planes have hit the buildings.
If it was a controlled demolition, then the ruptures and crumblings could have started from any other floors.
Now both these towers had more than 100 floors, so in any one tower the probability of this being a pure coincidence or overlapping stands the chances of being possible only once in hundred attempts = (1/100).
Similarly in the other tower also the probability of this being a pure coincidence or overlapping stands the same chances of being possible only once in hundred attempts = (1/100).
As the two towers had gone down within the same set of attempts, then the probability of this being a pure coincidence or overlapping stands the chances of being possible only once in ten thousand attempts = (1/(100)*(100)) = (1/10000).
This may explain that the Joint Front of terrorists with insider collaborators shall need to repeatedly attempt 10000 of such performances randomly again and again to be successful only once, where a conspiracy may look like a genuine case of terrorism.
With Regards...