Well my experience with being interogated was not for spotting but for bringing my flight bag onto a plane.
I was flying from PHX
last August and had my flight bag as a carryon item(that bag was worth more than my car at the time and I wasn't going to let it out of my sight). I had a manual for a Cessna Caravan, my logbook, pilot's certificate, medical certificate, charts, appoach plates and other such documents. Anyway, the screeners decided I was a threat to the flight and had me detained for 8 hours pending verification of my identification. Once they decided to compare my passport, driver's liscence, pilot certificate, medical certificate, EMT certificate and ID
from the EMs provider I was working for(badge included) they let me go. It seems that they are going a little to far!