(“. . . catch the evasion at the earliest possible moment.”)

Let’s start with two principles. When you’re training, a little bit of something good is far more useful than a lot of something that gradually deteriorates as you go along. And second, various exercises “cross fertilize.” Having the essence of one movement—the engagement and balance of a shoulder in, for instance—alive within your medium trot makes the quality of the trot that much better. Likewise, the medium’s forward thought should be evident in a good shoulder in.

There is a whole set of exercises which combine these two principles. In aggregate they are known as “staircase exercises.” The diagrams show where they get their name.In the first example the horse turns onto the centerline and leg yields to the right. If he begins to lose his balance or fall onto his outside shoulder, the rider sends the horse forward and straight on a new line parallel to the original centerline. Wash, rinse, repeat as necessary. Always catch the evasion at the earliest possible moment.

An interesting variation when the leg yielding is being successful is to interrupt it with a brief medium trot on the parallel line, re-balance, and then leg yield again.

Shoulder in to half pass to shoulder in is another good staircase exercise. The shoulder in sets up the bend and alignment for the half pass. Going back to the shoulder ridden on the parallel line to the first one reinforces the bend which you may tend to lose and keeps the horse correctly in the outside rein. When you do this exercise, your horse should maintain his same alignment to the grid. Don’t let his hindquarters yaw to the inside during the half pass or swing to the outside in the shoulder in. Keep him between both legs.

These are just two mutually reinforcing uses for the staircase. There are many others which you can combine creatively to keep your horse attentive and consistently on the aids.