The problem with TSA is that they have to follow guidelines and they're so scrutinized and observed every minute they work. Even though the actual agent examining your bag has enough common sense to know it's not a real grenade, his supervisor might be a complete "by the book idiot" and decide your acting inappropriately and that's all they need to detain you. Also remember that these people are trained not to be free thinkers and more like paranoid robots. Reason I'm taking this angle is I used to work side by side with them and heard many of them tell me why they act like they do. I used to be a technician in charge of maintaining and implementing X-ray, metal detector, and body scanner machines in an airport. People might make fun of the way they act and operate, but when your actions could be the cause of hundreds of men, women, and children being blown up you tend to take it seriously. If you want to complain and criticize then your own government is who you need to look at. They're the ones that not only implement these rules, but send in their own people to try and circumnavigate the systems set up in that airport. Now can you understand why they're paranoid? Any average Joe could be the one that they let through and the next thing they know they're filing for unemployment.