For my friend Yoav…I think you have many years to follow a choreograph program like i used to do in the early 90’s…You have to be a good quality trainer in order to follow all the Choreograph classes. They give you quality education and every 3 months you have to follow the new releases so you are keeping your quality live. You have to always be prepare and you know exactly that you are not doing something wrong. Its a lot of research beyond each release. Of course when you are a good trainer or instructor who follows a quality educational official training school like ACE , or ACSM then you know how to deliver quality workouts to your clients. But in both ways you have to Practice a lot!