Keeping in mind the concrete/steel core of both buildings as well.There is no way those buildings could free fall.
Bolts on the levels below were not effected by heat and would not all shear so easily. If all the bolts on the levels below were shearing there should have at least been resistance and considerable deceleration. But we didn't see that. We saw gravitational acceleration. No resistance at all.
It wasn't just bolts that sheared, it was whole colums. Columns should be buckling and that should be causing a massive deceleration.
Before 9/11, I didn't know what demolition squibs were. I didn't understand why I saw symetrically places puffs of smoke every 3rd floor or so, blowing out as the top of the building dropped.
Much love!