I experience this usually once a year (probably b/c I fly way too much...lol). Once out of DTW, I was just coming off a redeye from LAX, after getting to the gate of the connecting flight, there was announcement of secondary (security) at the gate upon boarding commencement. Either they weren't accepting digital boarding pass, or the DL app wasn't working, couldn't recall. Anyway, gate agents were giving me a hard time because I couldn't present a driver's license, as I gave them my GE ID. In the end, the TSA agent just looked at my bp.