We have pre-check status and didn't even know we had it. We were in the regular line at the airport and the security checkpoint guy told us we didn't even have to be in that line; he told us to notice the little "precheck" stamp. We are assuming that because Hubby recently got approved for a green card (so they have ALL of our personal info) that they automatically assigned us pre-check status.
Anyway, we now go to the short or NO line. And I DO appreciate not having to disrobe or pull out my laptop.
BUT precheck does not prevent you from being randomly pulled for the strip search. On our last trip, after going through precheck, Hubby got the random RED light flag at the x-ray counter and had to go through the manual search. I sat and video'd the whole 15 minute ordeal. I'm glad we were not rushing to a flight that day.