I opted out at IND a week ago. As gropes go, it was okay, but it seemed designed to be public shaming for disobedience.
I politely said, "I need to opt out" and was quietly told to stand right behind the radiation machine while we waited for a female to be available.
I could see my stuff causing a pileup in the X-ray belt, but I wasn't allowed to get anything and no one got it for me. I could see the bin that my Macbook was in but couldn't see the actual computer, so I spent the entire time watching that bin to make sure the computer never left it.
When the female TSO came, we moved away from the machine to a very public area, in full view of other passengers. I was intent on watching the Macbook bin so wasn't aware of the audience's reaction during the search, but afterwards another traveler told me with anger that the process was "ridiculous." I don't know if she had gotten groped herself or was upset that I had been searched so thoroughly in public.
The female TSO was polite and a little apologetic. I'm not shy about my body but even for me it was uncomfortable to have a stranger drag her hands across and under my breasts while other strangers watched. My top was just a t-shirt because the TSOs had told me to remove my vest.
While I was getting my stuff, an elderly French-speaking man was getting ruder treatment. He didn't understand English and went into the machine with things in his pockets. "Multiple anomalies!" a TSO bellowed. "We need a pat-down!" The little old guy stood looking confused and completely harmless while annoyed TSOs barked loud commands at him, apparently thinking he would understand English if they yelled it. It was ugly and shaming. Finally a traveler (family member?) who spoke French came up to help and the TSOs calmed down.
Even though my TSO was polite, the process itself appears to be designed as intentional public humiliation.