Teaching is hard. I understand the impetus to filter out students that are less naturally inclined to it, and if your goal is to establish something of a progr

Teaching is hard. I understand the impetus to filter out students that are less naturally inclined to it, and if your goal is to establish something of a programming conservatory, then administering a test like this would be an effective barrier. However, I think perhaps more advantageous reading of these results would be to recognize that the ability for students to construct these mental models is the single most important foundation in their education. Anecdotally, I have had some experience teaching non-programmers basic programming skills at the university level, and it's absolutely the case that some kids, even bright ones, struggle greatly with these constructs at first. They look at the symbols and freeze, intimidated by the arcane expressions, and control flow is often non-intuitive to them. To me at least, that's a pedagogical challenge, not a lost cause. You should have seen the exclamations of wonder and excitement when some of them finally got it, once a particular way of illustrating it stuck for them.