I interpret "resistance" to mean when the TSO's hand can no longer freely move up my leg. Therefore, I squeeze my thighs together. Of my last dozen or so opt outs, only one has asked for me to spread my legs. I ask, "are you going to touch my testicles and penis?" His answer of course was, "no". My response, which actually ended the pat down was, "the TSO in Chicago told me he wouldn't touch me either. So I had to report him." And the funny thing is, the TSO at ORD not only remembers me, but colleagues have heard him talk about me when we go through security together. After the ORD incident is when I started the "thigh squeeze."

Thus, I would like to direct any of those "in the know" to answer OP's #2. I believe, and have no evidence to the contrary, that "resistance" does in fact include thighs pressed together.