The eggbut snaffle, or any other middle-jointed snaffle can put extreme pressure on the
bars, often causing bruising, and also can inflict injury to the roof of the
mouth as the joint rises and presses into the palate when pressure is applied to
the reins, as the bars are squeezed. This causes raising of the head in response
to the pain, which is why a double bridle works with a head lowering and a head
raising bit together to achieve the desired balance in skilled hands
