I think all of this is important. Being able to understand or deliver a good performance is part of being a good actor. Learning to sing, dance, horse riding, fight are all skills. They will help you in some way or the other. If you are a good dancer, it will add grace to many other things, and not just your dance. It helps your performance even when you are not doing that particular thing. I had learnt stunts before QSQT. I think it did help me to have a basic understanding of stunts.