How does the horse's speed during boxing affect the quality of the work?

Speed management during boxing is one of the subtler aspects of the phase and one that many developing horse-and-rider combinations handle incorrectly by defaulting to either too much speed or too little. The ideal speed during boxing is determined entirely by the cow — the horse should match the cow's pace precisely, neither running ahead of it nor lagging behind. A horse that works at the right speed for the cow in front of it looks like it is working effortlessly; a horse that is at the wrong speed always looks like it is either chasing or being chased. Too much speed is the more common fault in horses that are naturally keen and athletic. A horse that anticipates the cow correctly but moves with more speed than the cow requires overruns to the side, either arriving at the blocking position too early and pushing through it or running past the cow entirely. The result is a horse that is always adjusting after going too far rather than holding a consistent, controlled position. In scoring terms, a horse that overruns repeatedly during boxing is showing a lack of rate that costs points regardless of how athletic the movements look. Too little speed creates the opposite problem. A horse that drifts laterally at a slow pace in front of a quick cow is always behind the cow's movement, and eventually the cow finds an opening and escapes around the horse before the correction can be made. A horse that consistently reacts late during boxing has not developed the degree of cow awareness needed to move proactively rather than reactively. The key to correct speed during boxing is teaching the horse to read the cow's pace and mirror it rather than working at a self-selected pace. This develops through repetition on cattle of varying speeds, with the rider reinforcing pace adjustments through quiet rein and leg corrections that teach the horse to calibrate its energy to the animal in front of it.