That article does not understand software economics. COCOMO is used as a very rough estimate for early development, when most of the work is cookie-cutter code. It is also generally disputed and not viewed as accurate for projecting real effort. For that matter, LOC is not a particularly good metric for assessing a code base: not for assessing concepts of "maintainability" or "cost" or "defect rate" or any other metric of code health. It is often used as a base starting point (i.e., given everything else being identical, a code base 2x as large will cost roughly 2x as much), but all the other factors are often considered more important. "All the other factors" include things like modularity, code complexity (many methods of measurement), token count (similar to line count, but not just measuring lines; i.e., some lines have a LOT of tokens, while other lines have only one token), and more.
I used to work for a company that had many patents around concepts of code complexity. We were one of many companies with a "cost estimator" tool, too. And we all knew (and openly admitted) that our estimator (just like all others) was very, very, very rough. I.e., cost could easily be 50% of our estimate or 2x our estimate -- the statistical deviation was wide. Our statistical relevance was so-so at best. Same with other models. Finance people still loved the models because you have to assess cost projections somehow, even when you know the estimates are widely flawed.
Side note: this is one of the many "holy grail" targets. If you can make an accurate (good luck) cost projection tool to help organizations identify "cost to complete a software project," then you have a product you can sell for $$. Just don't step into the ring assuming that nobody has tried. There are literally dozens of companies shilling various models, and they all sorta suck. Very wide margins-of-error (statistical deviations). As of a couple years ago, there was not a product in existence that is substantially more accurate than quality engineering managers giving a "guestimate" based on decades of experience. Some companies sell massive reports that combine all of the current estimation methods (we sold our estimates to a couple prominent report-generation companies, like Black Duck), but there is no single "this number is pretty good" solution. At least not as of ~2 years ago; last time I was working in that field....
