It is easy to spin wild scenarios of how some systems might hypothetically remain safe by remaining secret. Indeed, some of these scenarios will keep your office mates or even your casual end users from breaking into systems. But reverse engineering, loose lips, and black box analysis are so common that you shouldn't trust security through obscurity.

The security of serious protocols and algorithms comes from the inherent mathematical strength of their workings, and in the quality and integrity of the keys used by the protocols. Keep your keys secret (and do so effectively); make your algorithms public to the world!