Yeesh, people... this is NOT about looking for happy or unhappy people. It's about reading people. We all do it to one extent or another. Sometimes you can tell that somebody's mannerisms, expressions, personality... just doesn't fit right with who they are, what they're doing or what's going on around them...
It's not mind reading or thought police. It's seeing somebody in the line or in the waiting area that seems to have a different plan than everybody else getting on that plane.
I do not have faith that the current TSA clerk could possibly have the skills to do this with 16 hours of training.
On second thought, I guess you have a valid point. I’ve learned to read my kids for instance, but they aren’t terrorists.
It’s just that many airport security officers are ham handed buffoons.