[nickpsecurity]

It's in fact a long-established technique in high-assurance systems going back to I think aerospace or security-critical where the triple-modular redundancy trick was reapplied with separate teams building each one. Security through diversity also re-emerged relatively recently as a very active sub-field of INFOSEC/IT. If you're interested in that stuff, use these terms in various combination when you're Googling: "artificial diversity," "automated obfuscation," "moving target software security," "security diversity software." Also, including "pdf" helps given most good ones are papers. The word "survey" will occasionally land you on a pile of gold with references all in one spot. :)

Happy hunting!