DS is ambivalent, partly because he is shy about being recorded and he gets kind of lonely working alone. You are correct that there can be a benefit to self-study time and it's great that your DD can use the duplicate journaling time productively. In DS' case, he will have to work on his instrument on specific assigned music during class time in order to get credit for the course. It might reduce his at-home practice time a little but not much because he will still need to comply with the 2-hour weekly minimum on his logs and he wouldn't lie. It may end up working out well though so we will just have to see what DS decides.