One advantage is making sure that those on the quicker end of the bell curve don't have their time wasted. Not just in classes, but later on with their colleagu

One advantage is making sure that those on the quicker end of the bell curve don't have their time wasted. Not just in classes, but later on with their colleagues: If you know everybody can make the same jumps you can, then you can explain your thought processes without having to jump back and remind people of things. In addition, this helps everybody see each other as colleagues and peers rather than creating a weird situation where some people who are nominally on the same level end up being teachers or tutors rather than peers. It also helps create and set norms around what information people should know or be able to find as opposed to 'John can't search a database' or 'Cindy shows up without knowing first order logic and derails our presentation asking about it every slide'. Not providing some kind of weeding out/gatekeeping is a great way to disincentivize the talented because then they spend their careers as teachers or hand-holders instead of what they actually want to do + they end up frustrated having to slow down.