Comment 12 Factor (Score 1) 101
This is "ok" at best, but I'd prefer a more practical guideline, and for that Adam Wiggins' 12 Factors are a much better place to start for scalable web systems: http://12factor.net/
The rule on staying alive as a program manager is to give 'em a number or give 'em a date, but never give 'em both at once.