''We built in enough redundancy to allow entire portions of floors to be removed without affecting the building's structural integrity, on the assumption that someone might need double-height floors,'' said Larry Silverstein, president of the company. ''Sure enough, Salomon had that need. Source: http://query.nytimes.com/gst/fullpage.html?res=950DEFDD113BF93AA25751C0A96F948260&sec=&spon=&pagewanted=1

The comment and NY Times article above completely brings into question the fire/gravity reason for the collapse of WTC 7.