Physics of the 9/11 building collapses?



I find some of the suggestions of the producer of this video to be rather
hard to fathom. OTOH, I have to wonder about the symmetry of the
collapses.

http://video.google.com/videoplay?docid=6323427897709690102&pl=true
--
http://www.vho.org/GB/c/DC/gcgvcole.html
http://www.vho.org/GB/Books/dth/
http://www.germarrudolf.com/
http://www.ice.gov/graphics/news/newsreleases/articles/051115chicago.htm
.