FliesWay2Much,

I think that's almost giving them too much credit. In my limited experience, the guy was clueless and taking forever. He wouldn't have been able to catch anything.

But I'm stuck on the idea that behavior detection questions are a form of screening, and this screening is taking place before the TSA has jurisdiction.

I agree with you that the behavior detection officer is far more likely to catch someone with a problem unrelated to aviation safety... if the officer catches anyone at all.

We've known for decades that behavioral techniques don't work.

Have a look at Kraut & Poe's landmark study from 1980:
http://kraut.hciresearch.org/sites/k...nJudgments.pdf

This was a mock customs inspection in which travellers were given fake contraband, and judgments of their behavior were made by customs inspectors versus "laymen." Behavior predicted if a passenger would be searched, not that he or she was carrying contraband: