Real life is all about trade-offs. "Slow" and "expensive" is not an option if you want ot be competitive, and others can do it fast and cheap. If all you have to go on is smoke, then learn to recognise different kinds of smoke is pretty handy.

In hindsight, more than a year after writing this article, I would say that this list might be most useful for the business guy to recognise someone who will help him hire good programmers, rather than as a direct hiring tool.