Well there's your answer right?I am of course aware of this part of the explanation. I think it is fascinating. I agree with you that it should be common knowledge; there should be a lot of popular science writing about it.
It amazes me that such large buildings were vulnerable to this kind of failure, and that it was part of the design of the buildings. Not that they were designed to fail like this, but that understanding their failure follows straightforwardly from understanding their design.
It raises a whole bunch of questions for me. But it doesn't sound like you're proposing to get into a discussion of them. I just wanted to say that, yes, I have heard about the 29,000,000 pounds. Thank you.
In order to prevent the collapse they should have designed floors to resist 29,000,000 pounds times whatever safety factor.