I normally complete the next "recommended" skill indicated by the red star. Rarely is that a skill that I have already completed. Should I be returning to those previous skills randomly whenever I feel like it in order to master them? Or will the system eventually recommend that I return to them?
That's what I thought, but a few times the red star has actually recommended a previously completed skill. So, perhaps they are working on recommendations to return you to those previous skills. I also noticed that when I go back, the repeated skill incorporates some of the new material I have learned. Very smart software!