I've seen quite a bit regarding this subject. I have worked in construction for 47 years now and I know what is possible and what's not. The twin towers were not controlled demolition in my opinion. Building 7 was, that's my opinion. Introduction of massive damage and a live load in a way that was not in the original design would bring those 2 towers down.

Regarding building 7, controlled demolition from the top level/ center of the building would create a live load that would require less input to bring subsequent levels down.