It promotes a lot of unhealthy behavior in terms of course choices, that is for sure. And no one even knows for sure if they are val or sal until after college admission results are in. One of my brothers was a joint “val” with a few others in his large high school class, and I still remember all the kvetching that went on among the students and parents about who took which classes, etc. It was unpleasant and didn’t do anyone any good, IMHO.