There are large groups of techniques in patterns that are very similar to one another. It makes sense to practice them together, as the use much the same muscle groups and trajectories, with only a few differences in tool, height and stance. This group is the straight armed punches and thrusts – they make up 25% of the colour belt patterns. So with a few minutes’ work a quarter of the movements between Chon-Ji and Choong-Moo tuls can be practiced efficiently and quickly.