Sing, My Murdered Darlings

It begins and ends with a flash of light, the last thing remembered by anyone using d-mat. A flash of perfectly white light issuing from all eight corners of the booth that somehow doesn't leave an afterimage. People never talk about the last part, which is symptomatic of their willingness to ignore the discomfiting obvious. The flash of light is their final memory before they're torn into atoms. It's also the first thing they see when a perfect replica of their brain comes alive at the other end of their journey. However, what they think of as a single, near-instantaneous event is actually the beginning and end of a two-minute process that a philosopher much smarter than I once described as "the most savage evisceration imaginable".
My darlings will endure much, provided they forget entirely afterwards.