<font face="Verdana, Arial, Helvetica, sans-serif" size="2">Originally posted by cordelli:
They say it's because it's easy to conceal something in the bag and have it masked by the laptop.
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As a former TSA person (and glad to be former) that is true- a laptop in a bag makes it very hard to see what else is in the bag. Other electronics lack the density of the laptop and you can see through most of them pretty easily.
As the other poster mentioned a large stack of magazines or books can hide some things as well. But only some types of objects. And if you have enough papers together you are likely to get searched because that can look suspicious on some X-ray equipment.
At my airport we tried to have someone out in front of the checkpoint to ask about laptops. The frequent travelers we didn't have to talk to as they typically were doing the drill before we got to talk to them. Plus after you worked a while you got to know them- you saw the same folks every week. We concentrated on the infrequent fliers because they did not know the process. This was to done on a conversional, one to one basis. No yelling which we would have considered bad customer service.
I disagreed with lots of TSA procedures but the laptops out rule was not one of them. There were valid technical reasons for it.