The question is, how could ENOUGH of the columns fail so quickly that a symmetrical collapse is produced. There's a large time span, so perhaps some kind of argument could be made that sequential losses of columns' structural integrity occurred relatively slowly, but that a critical number was attained only over a brief time span. Why was the BBC not astute enough to ask a rather obvious question of Dr. Sunder? Especially since they interview ae911truth's Kamal Obeid, a structural engineer, who expresses doubt that simultaneous collapse of all columns is possible, even if local failures of one or two are not. Instead, they have incorporated a non-explanation explanation into their show.