I hope it is standard practice to require some initiative of students. The "topics" of a course are about learning, not teaching. There are a lot of techniques by which students learn that don't, for example, require explicit instruction - especially lecture.
On the other hand, the expectations need to be clear. If the instructor "teaches" R by pointing to the documentation and then requiring its use, that may well be appropriate. I would hope that they answer questions from students about it, however.
My mantra in teaching was always that what the students did to learn was more important than whatever it was that I did. I had to "set the conditions" in which learning would most likely occur, but not everything that the student learned need to come from my pen or mouth.
Learning how to learn is probably the most important lesson taught at university. Learning how to listen should be a skill already learned that needn't, necessarily, have further reinforcement.