Here's a mental exercise. Imagine only the four corners of WTC7 standing alone with no structure between. Then suddenly they all fall down together like mirror images of each other. This is completely impossibe you say ? Can't possibly happen.
Okay then. Now mentally add some structure between the four corners that will cause all four corners to fall down simultaneously like mirror images of each other.
Tough, ain't it ?
Anyway, If a person had a good video of the collapse of WTC7 they could overlay a thick red line along any visible roofline and call it say a ' brush handle '. Then they show the collapse and demonstrate that the bush handle does not roll off or tilt showing that he corners collapsed simltaneously.
Then they could ask the viewers how the collapsing steel inside all collapsed at the same time. All 40,0000 tons of it.