Instead of repetitions though, I usually tell my students to time themselves, with the amount of time spent on something depending on how difficult the passage is, and how large a tempo the student can play it at.

Usually no longer than 5 minutes on one specific thing.

Your insights into practice scheduling and the inner mechanics of practicing are wonderful. I have found that this very topic is one of the hardest things for me to get a good grasp of. I am mostly self taught and have a great deal of information about what to do but not so much about how to do it and put it together into a workable routine, which is pretty fundamental to improving (I believe).

Many thanks.