You could be right, I am not privvy to all of the intel we get. I used to carry tons of stuff in the collar of my uni when we were hot or on patrol in Haiti - not explosives, but weapons and tools of all sorts. TSA is the ONLY place that I have seen collars routinely checked while entering. You may say that many of the possible threats are not likely to materialize, but the Trojan horse only had to work once to change history. We could argue that there are/aren't people out there trying to do harm to aviation all day. There is a ton of evidence for both sides of that argument, the bigger question is what is the tipping point on security? I don't think we are there yet, but the question shouldn't be how far can we go as an organization without serious pushback from the public - on the contrary, it should be how do we do the core mission assigned and provide the best security while causing the least amount of problems for the passengers.