TSA screeners and behavior detection officers may give you extra attention if you complain about security protocols (video at the jump). Former FBI agent Michael German sums up my feelings pretty well:
It’s circular reasoning where, you know, I’m going to ask someone to surrender their rights; if they refuse, that’s evidence that I need to take their rights away from them. And it’s simply inappropriate.
In related news, the GAO recently told Congress that the TSA’s Screening Passengers by Observation Technique (SPOT) is not scientifically grounded. The GAO testimony is available here.