"Why did you avoid the empirical evidence? ... How can you claim the Towers fell at "free fall rates, when it's obvious that debris ejected from the top of the Tower, which represents pure free fall speed, reaches the ground before the rest of the Tower?"
Yes, indeed. How about you showing some intellectual honesty and apply some physics to that emperical evidence of the ejected debris?
Calculate the horizontal velocity of some of that debris. Then explain where that energy came from.
Recognize that it takes energy to eject it as such, energy that is then no longer available to be accelerate downward at free-fall rates.
Recognize that the energy consumed by pulverization of content in the path of greatest resistance is then no longer available to accerlerate the mass downward at free-fall rates.
Recognize that the debris eject is no longer available to be used as a pile driver to help pulverize the lower floors.
Recognize from that emperical evidence that the upper floors inexplicably (unless you're willing to consider explosives) "accordian" in on themselves before the collapse goes through the floors where the impact occured.
Recognize that the inflated times you've given for the collapse are without basis, because even you admit that you can't see what goes on at the bottom behind the dust clouds. Therefore, be intellectually honest and time the stages of collapse that you can effectively observe and scale, like the accordianing upper floors and the collapse of all floors down to a height effectively calibrated from surrounding buildings or other benchmarks.
All of that said about elements in the destruction that suck energy away from the towers being able to fall at free-fall, the 9/11 Commission Report -- using numbers provided by NIST -- documents the collapse time remarkably close to calculated free-fall. And as was already mentioned somewhere above, your inflated collapse times themselves are closer to free-fall rates that what most architects, engineers, and physicists would calculate based on the resistance and other load bearing characteristics of the materials in the path of greatest resistance.
And if the WTC-1/2 dust clouds confuse you in your efforts to clock free-fall rates, look no further than WTC-7. How many stages did NIST document, what were their collapse times, and how close were each of them to free-fall?
Be a man of your word and be done with me.~TwentyTen