Not sure about that. The reason I personally only write comments occasionally is that the code changes and the more comments there are, the less likely they'll be maintained along with the code.<p>If I'm going to make a comment, it better be worthwhile. A heuristic I find useful is "why, not what". That is, if the code has an unusual but justified feature, place that justification in a comment.<p>Sounds like the author is waist-deep in a crusty old codebase, but I'm not sure comments on every line are necessarily the solution.