I don't discuss the rate of fall. But menton of the higgh rate of fall, whatever it is happens to be integral to the thread becase that is what we are trying to feasibly explain.
Rates of fall are one thing, how they are created is another. A building with a single story could be blown up and the rate of fall would not be an issue due to elevation because the visual explosion would rule.
In the case of a tower the visual event is also important and can influence understanding the rate of fall as well as the determination of collapse or demolition.
They tell us "at least ten years" here.
http://www.ribbands.co.uk/prdpages/C4.htm
It is not a theory.
The C4 is not encapsulated in a slurry form. I feel that C4 would not detonate in that form. A slurry is created from CC4, the rebar dipped in it and then hung to dry. Once the excess solvent has evaporated, returning it to viable explosive form, it is then cast into concrete.
I learned of the process from a magazine article published in the early 1970's which described how navy seal divers discovered and used the process without orders to stay off the bottom using a jack hammer knocking a hole in a sub base wall that engineers were trying to keep secret by not putting on the first set of plans.
They were caught setting off ordinanace without orders, gave up their information to an investigating officer who then handed it to explosives engineers who then developed it into a widespread construction method for self destruct sub bases and missle silos.