If what you are measuring doesn't give you data you can really make decisions with, it is worse than no data. You'll be tempted to make a decision because you have that data.
BTW, this is one of my startup rules: measure what's important. Decide what's important by how it would affect your decision-making.
Sure, but there's an order of magnitude difference in average difficulty (at least) per LoC in legacy maintenance vs. green-field development, and most software jobs are in the former camp. It's true that 20-40 LoC/day is a fast clip in most of the software industry; it's not true that this results from laziness or too many meetings.
Hacker News gives us a rose-colored view of the software industry-- one in which knowing about functional programming and agile methodologies (regardless of whether one intends to use them) is a prerequisite for being considered literate, and in which 200 line-per-day development on new invention is something people can actually get paid for. That's now how the average developer experiences software.