Problems: 1. He quantifies productivity in lines of code. 2. By doing so, he only considers the development but not the maintenance cost of software. 3. He is not even internally consistent. He states pair programmers are 15% slower than individual programmers but then lists then as only creating 75% of the LOC an individual programmer does. 4. He pulled that number out of nowhere to begin with. The only referenced papers are his own. 5. The numbers given for errors are equally bogus. 6. At no point does he define his different tiers of programmer(novice, average, expert). 7. It would seem he assumes the same wage for all three tiers, which is completely unrealistic. 8. Point 7 being the case, the conclusion of the entire paper is that the best thing to do is hire a bunch of expert programmer to replace your average ones while paying them the same wage. Even thinking that you can identify with a high level of certainty who truly great programmers are is a rather lofty goal, and pg has an article or two talking about how difficult it can be. Add to that the fact that even google has come out recently and said that their methods of interviewing programmers has largely failed to identify those that would be successful at their company.
