Sorry if this has already been said, but good geometry is not just about riding tests – it’s part of every training ride. A round circle means that the horse is holding consistent rhythm, consistent balance, consistent bend – and with that, probably consistent pace, consistent contact, etc. When a horse deviates from any line – straight or curved – it means that there has been a momentary loss of at least one of the above. (Notice how bobbles and bulges tend to happen after transitions between and within gaits.) I always heard the adage about “if you don’t have a fancy mover, you can make up for it by riding an accurate test” as meaning that at least you have some element to improve your score. Now I understand it as, if your horse isn’t a naturally beautiful mover, riding good geometry means they maintain consistent rhythm, balance, contact, etc., – IOW, become better movers. Also – riding consistent, predictable lines helps the horse a LOT mentally. If your aids are asking for a nice consistent bend, or straightness, you develop that “dialogue” with a horse. When you allow them to wobble and fall out, it’s sending an inconsistent message. I ride an anxious one, and paying attention to my geometry – like, every single stride – really helps her to relax and focus her mind.