>Documents work >> because you can use them early (models that build knowledge), >> because they persist (you're not crippled by your imperfect memory), >> because they're efficient (you don't have to keep repeating the same >> conversation with perfect fidelity), because they can capture >> details (not just vague impressions), because they can be reviewed, >> critiqued, and corrected (unlike your trembling thoughts), because >> they remain (unlike you, you job-hopper!), etc.
Excellent points. Extreme programming demands this of the code as well as any documents the customer may require.