1. Note the single, isolated, high-speed ejection of almost clear debris (glass only?) at mark ~:09, even with the narrow windows on the dark building on the left.

2. Note the upwards appearing movement of the dust ejections. Does this indicate great heat? Perhaps the demolition is being directed upwards from the floor pans, pulverizing concrete, leaving the window openings on an angle?

3. Note the rapid downward progression that appears to be much faster than gravity or an interior floor collapse.

4. Note the sequences of small violent ejections and then a large ejection. Perhaps this is evidence of a every third floor attack plan to take advantage of structural connection points? If you freeze at :09 it appears they are offset top to bottom as we would expect from the grid pattern of exterior panels.

Now I understand why there are few pieces of concrete floor. Now I understand how 1/2" fragments of bone were discovered atop the Deutsche Bank Building. . Now I understand why much of this debris ended up in the lungs of the poor souls trapped in the advancing cloud.

Let us never forget the human dimension.