It's not as strong a hint as you think. I've interviewed and worked with a fair number of programmers myself, and I can say equally definitively that the best o

It's not as strong a hint as you think. I've interviewed and worked with a fair number of programmers myself, and I can say equally definitively that the best ones know how to program in Lisp, and the worst ones do not. All we see is that the programmer who is motivated to teach herself C or Lisp (or any other "difficult") is a better programmer than the programmer who is not. Which, on further reflection, is almost self-evident. Of course programmers who are motivated to keep learning and keep practicing become more skilled. But it doesn't make any special claim about the benefit of C in particular. Coming at it from another angle, have you worked with a lot of electrical or computer engineers? C, in many cases, is the highest-level language they know. From personal experience, I can tell you that their code is no better (and in many cases, considerably worse) than code written people who've had experience with languages at the top of the abstraction hierarchy. EDIT: And, of course, I scroll down to see that tptacek has already made this exact point, and more eloquently, to boot.