Part 3: Greg discusses with the riders the best position for shortening the horse's stride between fences in the upcoming exercise, as well as lengthening. He gives a comprehensive overview of position, from hip angle to center of gravity, with thorough explanations of why he suggests each for any given situation and the importance of the aids being very clear. The riders warm up over a small vertical and Greg reminds them to apply the principles of more roundness and thoroughness that they worked on on the flat. He focuses on lead changes as a way to monitor the horse's submission and readiness to continue jumping.