It's all for show. We know it is because for $85 you can get out of a huge part of the screening. And to advertise it they randomly let people into the pre-check line when the regular lines get too long.
I happen to have global entry ($100 for 5 yrs) and the only things I get are a shorter line (usually), I don't have to take off my shoes/light jacket, I don't have to take out my laptop and I don't have to take out my 3oz liquids. I hardly see that as a huge reduction in security. It's just more convenient for me. Everything, including me, still goes through all the scanners and I still get pulled to the side now and then for a hand check. That's not a "huge" difference. Oh, and I can use the customs kiosk to get through customs a little faster because my fingerprints are on file. But I still had to do a hand check when I brought tulips home from Amsterdam and when the whole ebola thing made them ask everyone if they had been to Africa.