Not a whole lot new here. If the OP was pulled aside for a more rigorous search, that is a special case and not of interest to others unless it is being done to many people. I was once selected at FRA for a more rigorous search, but that does not cause me to say FRA is awful and I'll never go through FRA again. It's all anecdotal.
Apparently the OP's other complaint is that the immigration line was so short that he/she did not get sufficient benefit from bypassing it with Global Entry!
The only thing new here is the report that there was a third security check before the gate. (The first is after arrival on an incoming flight, and the second is before preclearance.) I hadn't heard that before, and the OP provides no details.
Originally Posted by
airbornedaddy
...you have no recourse.
The OP is a transfer passenger and has recourse---he/she could fly another airline. I am a transfer passenger also, I have GE, and I too don't like the idea of preclearance, but it doesn't seem like a big enough deal to affect my decision.