Quotes from the Masters Laterals 1

​François de la Guérinière
This exercise [shoulder in] has so many benefits that I regard it as the alpha and omega of all exercises for the horse which are intended to develop complete suppleness and perfect agility in all it’s parts.

Nuno Oliveira
In the shoulder-in hold your body against your outside elbow.

Charles Harris.
The most common fault made by riders in doing shoulder-in is to have the horse more bent in front of the wither (or saddle) than behind it. The horse must be the same in front of the withers (or saddle) as he is behind.

Nuno Oliveira
Correctly done the shoulder-in gives great results as it relaxes and straightens the horse.

Alois Podhajsky
The most important aid [in half pass] is given by the rider’s inside leg which pushes the horse forward and is responsible for correct bend.

Alois Podhajsky
The position of the [horse’s] head [in half pass] should be such that the neck is not more bent than the whole body.

Nuno Oliveira
Don’t exaggerate the bend in the half pass. Otherwise you block the inside shoulder.