[stevarino]

If this is the case (and I agree that it sounds likely) then what's the appropriate response from a bad guy? You don't take an action without considering a reaction...

Could this method be applied to fabric? Perhaps certain types of plastics? What if the bad guy hints that this is their plan with no actual intent other than misdirection. This could overwhelm screening resources, frustrating passengers, and stressing security agents while the actual threat could travel through another means, if it exists at all.

I traveled this weekend and can't help performing threat analysis against these security models. It's never made me feel better.