Disappearing's Self-Destructing Email: Just Key Escrow?

A researcher has questioned the claims by San Francisco start-up Disappearing Inc that its self-destructing electronic documents represent a great leap forward. "All Disappearing Inc offers is a variant of third party key escrow and nothing more," wrote Brad Arkin of Reliable Software Technologies Corp's Software Security Group in a posting to the comp.risks mailing list. "The problems with key escrow have been well documented. By forcing users to go across the network to retrieve a key (which may have already expired) every time they want to read a locally stored message, it is a certainty that users will instead simply cut and past worth reading again into a plaintext file outside the control of Disappearing Inc's encryption." Arkin urges users to cut out the middleman and use a package like PGP instead.