The last time I went through Ontario,CA as a pax, I presented my TSA pre-check Global Entry ID card, and the person did not know what it was, nor did the supervisor!!!! I was , am still flabbergasted at that one.

I am a platinum elite on Delta, and never get challenged about anything at participating airports when traveling on Delta. Waltz right through. Well, I am not an elite member on United, and get the full finger wave each time I travel on United. I think you have to be an elite status member on each airline for the TSA pre-check to help. Makes no sense to me, we've been checked, and heavy checked, and "D" checked, and still treated like a common criminal.