I fly through TBIT often. I actually said some nice things about TSA at that specific location in the past but it has gone to hell over the last year. Still, for the most part they have tacitly allowed self opt-out since the radiation scanners were deployed. I have been directed to their radiation strip search scanners a number of times so far but have never been challenged 'yet' when I just kind of aimlessly wandered to a WTMD when I reached the end of the radiation line. Last time a month ago they did have a TSO selecting victims from the WTMD line and this represented a change but I gave her a silent "don't you dare select me or there will be trouble" dirty look and she passed me by and I went through the WTMD.
I'll be through TBIT again next week. I will opt out if I can't self opt out as usual and if I have to I will make a scene to make it worth my while if they inconvenience me. Unfortunately for them I am to shameless to be sexually humiliated into submission.