Just in a similar line to what the previous post says, I had a somewhat interesting experience at NRT with an extremely polite security screener (as they almost always are at NRT, I have to admit).

It was a bag search cause by their inability to identify on their X-ray equipment a pair of tweezers in my hand luggage as a pair of tweezers. The unusual thing was that the reaction in my head - I was not bothered about being delayed, and I was not bothered about having my bag rummaged through, all because the screener was so polite and apologetic about holding me up while they just wanted to identify what thy couldn't identify on the X-ray was.

I wasn't much help because I never thought that the issue was my pair of tweezers so I was utterly baffled (I have travelled a lot with those pair of tweezers so I assumed the could tell what it was), but something really struck me.

When a similar delay happened in Australia and the security officer was arrogant and irritating, I found it annoying although I showed no reaction as they were only doing there job, whereas at NRT, I almost felt bad about having this 'unidentifiable object' because she had a 'I am here to serve the passengers' attitude.

What a difference it makes when you are spoken to politely, and when the officers' general demeanour is that of a good attitude!