So a friend and I wanted to find a way to work on our tournament katas on days when our head instructor was out. We started taking turns filming ourselves doing them over and over, critiquing one thing at a time. This seems to work great, I have seen a huge improvement in my advanced Katas like Sepai/Kururunfa/Seyunchin. Not only that, its also very beneficial to film your sparring sessions to pick up on mistakes you do and improve them. Anyone else every try this?