I will admit I didn’t read the entire post(Waaaay too long). I may not even be hitting on the right point. All I know,from what I got from the first part of the post,is ridiculous. Again,if I’m missing the point,I’m sorry. All I want to say is I work with concrete,and I know what happens when it’s exposed to high heat.It literally busts,explodes.Especially from the EXTREME heat it would be exposed to from all the burning jet fuel. The concrete would have lost it’s structural integrity,and no steel in the world would keep that building up. As far as this guy being an engineer,my boss likes to say " An engineer is like a guy who knows 50 ways to make love,but doesn’t know any women". I’d like to tell the author,welcome to the real world.