The shoulder is a point of balance for an animal. Reward animals that move in the correct direction by releasing some pressure on their flight zone. As long as you do not penetrate too deeply into the flight zone the livestock handler can quietly move animals. Penetrate too deep, by getting too close and the animal flees. In confined situations requiring humans to be in the flight zone, Temple Grandin has designed many chutes that curve like snakes.
Animals flow smoothly through solid sided, curved chutes.
The animals can not see you penetrating their flight zone because of the solid sides. The solid sides also prevent animals from being distracted by other outside movements and novelties. The benefits of solid sides are lost once a coat is hung on the chute or people begin sticking their arms into the chute while animals are trying to move. To promote the best movement, cattle should be able to see two to three cow lengths ahead. This is Grandin's standard design.