Both show, tell AND make them feel the techniques from both roles. And it is not telling how to do a technique if large portions of it is along the likes of "like this", even if you of course can use your voice to direkt visual focus. But as an experiment for the instructors at your academy, I really recommend trying to teach someone visually impaired or wearing a blind fold. Makes you do some extra thinking how to describe the techniques without relying on the visual. So when you do BOTH (as well as some hands on, helping them feel the technique), it's much more effective in making them grasp it. Of course you do aliveness, ecological and all the buzz words you want as well, but I believe your students still need strong fundamentals with technical and aware understanding of the basics and basic principles. I've met far too many practitioners (even high level BB:s) who have excellent technique but not necessarily are consciously aware of the details of what they're doing. Makes both self improvement and teaching others effectively more difficult.