When I’m teaching I am constantly checking to see if the rider is correctly balanced. Sometimes it is very obvious; if the rider is out of balance it will make the horse unbalanced and result in a crooked movement. Sometimes it is much more difficult to see; a slight shift in the riders weight can have a big effect on the horse.
If you think about carrying someone on your back, it’s easier to carry them if they hold themselves straight. If they grip with their legs, lean to the side or backwards, sag with a round back, it makes it much more difficult for you to move and you will be constantly struggling against their weight to move straight forward. It’s the same for your horse.
A classical position allows you to feel what is happening in your horse’s back and then you can make precise corrections. This position also allows you to move with your horse, so when he is making a movement, you can sit with him and don’t disrupt his flow.
Riders with a good stable classical position can use this to help their horse, but if the rider’s weight moves unintentionally, it unbalances their horse. A good position allows you to give light, precise well timed aids, and to have a flexible lower back that will follow your horse’s back, so you start to ride by feel.
Diane Followell Classical Dressage Trainer