this one is simple…ok well as you should know an instructor would NEVER do u wrong…i myself copy my instructor to a T to make sure im doing everything rite…so if ur instructors are moving upper body…why wouldnt you?? your colleague is very silly for telling you otherwise…and also, Dance in itself is an expression using your body parts…i havent never seen a great dancer that couldnt move at least a little bit of upper body…and yes latin dance is an erotic form of dance…upper body movement is a must have…the only dance i havent seen use upper body movement would be River Dancing lol 😀 but im sure u have already resolved this quesion but i just felt like putting my insight in 😀

I think this is advice given to beginners because in the beginning it’s very hard to separate upper body movement from lower body movement. At first, beginner’s tend to use their shoulders to help them move their hips. There is a difference between moving your upper body along with the music (which is what I am assuming you saw…) and moving your upper body to move your hips. I wouldn’t be surprised if later on your teacher might encourage you to be more “musical” about your dancing and encourage a some upper body movement. Still a newbie, but this is what I understand so far. 🙂