I opted out and got the pat-down at DTW, connecting after an international arrival. My wallets (I spread things among three during overseas travel) needed to be in a tub that the TSO took out of my sight and put through the x-ray. It was my dazed state after a long flight that made me forget things on me that set off the WTMD and got me the secondary; also if I'd been thinking more clearly I'd have insisted on counting all the money and cards in the wallets, but it looks like I got everything back o.k.