I mean, it sounds like it would be even better if the duress response was more subtle.

A duress code might let me wipe my phone when someone holds a gun to my head and demands I unlock it. Problem is, there’s still someone holding a gun to my head.

He had an e-reader and phone. My solution would be set the phone's duress pin to the e-reader's actual pin then consent to the e-reader search providing its pin and see what happens.

The actual solution is cloud backup + re-image after the border.