There are other measures the suspect could have taken; store everything on an always encrypted micro-SD, which is tiny enough to be easily destroyed.
Actually: Has anyone done any research about the risks of "super microscopes and Flash memory"? There's a theoretical risk with conventional platters. I don't know how big one bit is on a conventional drive, and I don't know how big one bit is on a, say, 8GB micro-sd card.
Obviously, if it's sensibly encrypted there's no point. But a person may think they have physically destroyed a flash drive only to have left information available.
Here's some links to DIY de-capping and microscopy of a variety of ICs: