Detection of contraband can be foiled in these systems
Ran into a friend who is a colege prof. and he told me about a peer reviewed (don't know what that means but he acted like it was a big deal) article that states the scanners won't see weapons or explosives on the side of the body or under rolls of fat. It was published in Oct. so may have been discussed here before but couldn't find it with a search. From the Journal of Transportation Security:
http://kochanski.org/gpk/misc/papers...arlson2010.pdf