>Two programmers working 20 hours a week, for example, are way less productive than one programmer working 40 hours a week. And the one programmer will learn fa

>Two programmers working 20 hours a week, for example, are way less productive than one programmer working 40 hours a week. And the one programmer will learn faster because she's putting in an extra 20 hours a week. From where did you pull out that data ? It is always possible that one programmer working 20 hours is more productive than two programmers working 40 hours. It depends what they are actually doing.