mmmnnn,
no offense, i saw said documentary, advocating the pancaking effect, and its balonely.
one floor slamming into the other?
wouldn't that leave a load of floors pilled up on the bottom, with the central column poking up through the top like a coctail stick through a party snack?
one floor hitting the other would reduce the descent of the building as it fell. it would incurr friction and shock.
the building fell at near gravitational speed.
the entire building, bar steel was atomised to dust. no furniture, no concrete slabs, no whole items, nothing. atomised.
collapse cannot do that
only massive energetic explosions do that.
look at the debri field as it drops. material is being ejected from the sides like a cannon, its ejecting at a hundred or more feet out...
you also have pipes and steam pipes (service pipes etc) cracking and bursting all over the building .
collapsing 'floors' from the top would not do this.
only a deliberate weaking of the skelatal structure through out the building could do this, initially with denotation cutters and then bigger charges uses to sever the main column, from the top down.
no offense again, but not factoring-in jet fuel into the equation of a plane-resistant designed building is ludicrous.
(jet fuel doesn't melt steel)
top down demolition.
Company that ran security of the WTC buildings tied to Marvin Bush, who had parallel contracts and dealings with the military and others (Securacom).
http://www.whatreallyhappened.com/911security.html