Thoughtful stuff a ever. As a TEFL teacher, teaching beginners, I always tried to make sure I was learning a language in a beginners class for the same reasons you outline. Hence I’m not very good at a number of languages 🙂

Phil Race in on his blog argues in a similar vein that “All teaching staff in higher education would be required to be students” and “Everyone would be required to spend some time teaching students and assessing their work” http://phil-race.co.uk/if-i-were-in-charge/