Sometimes when I show them the "Sentry" on the back, it helps. Sentry *is* listed on the TSA site.

At MIA last week, the TDC noted, "We just learned about these today". I was surprised that they didn't already know, since I thought MIA was one of the places where the GE card is supposed to allow you to go through without taking off your shoes. But looking at the website, I learned that it's just in the AA terminal where that's true, and I was flying DL.