Very many riders think that to inspire a horse to transition upwards they need to ask their horse to go faster. And when asking for a downward transition they need to ask their horse to go slower.
WHY I USE A FLAG IN TRAINING
HOLD ON KIV
STRAIGHTNESS AND EMOTIONS
While a horse is emotionally anxious I know there are many ways we can make crookedness uncomfortable enough to force its body to work with a fair degree of straightness. But I don’t believe that when a horse is emotionally anxious it can find straightness itself - we have to impose it. A chronically troubled horse will always be chronically crooked.