I am a frequent International Business (Class) traveler. I am also a Cancer survivor, so after a year of radiation therapy, I figure my body scoffs at whatever the TSA can throw at me. I just take whatever line is shortest – which usually turns out to be the one with the icky scanner.
I like to fly in painter/cargo pants, as that gives me places to keep my devices/wallet without having to get into my back pockets or sit on my stuff. I started to notice that when I wore cargo pants and went through the full body scanner, I got a patdown – every time. Regular pants were easy (except one time I forgot some paper money in a pocket – again with the full patdown).
The BusClass/Express security lines tend to have nicer agents than the usual cattle calls (suppose it helps when you deal with 5% of the people, most who know the drill inside and out). So, one day while getting my 5am patdown, I asked the agent what was up with cargo pants. He looked around shiftily to make sure no other agents were close by, then whispered “They can’t see through more than one thick or two thin layers of clothing, or a few pieces of paper. If we can’t see through all your clothes, we have to pat you down.”