It’s commonly acknowledged that traditional pedagogical methods emphasizing passive listening and rote memorization are suboptimal. “We now know” that there are superior methods that focus on student engagement and discussion. What I sometimes wonder is whether people in those benighted traditional days knew this as well. After all, it’s not as though the aspects of human nature that make active learning preferable just sprang up 20 years ago, and presumably everyone involved in a community of learning stumbles into a productive discussion at some point.
And then it hit me: the badness of traditional methods is a feature, not a bug. The goal is not so much to teach people as to sort them by ability. The truly gifted students will overcome the crappy pedagogy and learn the subject anyway, whereas the laggards will be revealed as the laggards they always were. The task is not instruction, but judgment.