The only problem i have with the TSA is when im a selectee, and they don't bother to give me extra screening. In LAS, when I wasn't called aside, I actually informed him I was a selectee, and the guy looked at me as if i was trying to cause a security issue. So i complied not being a selectee, informed the gate agent, and sure enough, after quite some TSA agents came out to "clear" us in front of all the passengers. Im glad i didn't have to make that long walk.

There is no real sneaking around this, if the terminal beeps and you dont have the evidence of actually receiving extra screening, they wont board you.