Not quite sure what point the author is trying to make? He agrees that lines of code are a bad measure of productivity because, yet claims that the average he computes can help him predict future development times. Then he explicitly points out that different parts of the codebase required different amounts of work, apparently unrelated to their code line count, yet does not relate this to the previously mentioned points. Also, what is up with the random comment about code coverage at the end? That doesnt fit in with the rest of the article either...