The ESS, Field/Show are two different dogs because:
For 57 years CH Championed dogs have been bred to comply with just a physical standard. When the standard no longer reflected the CH dogs, the standard was changed to reflect what was making the CH. Nowhere does this standard require any ability of a dog; it is all physical appearance. While for 57 years the Field people have breed a dog, for performance, leaving the physical appearance to fall where it may. The Field dog is bred considering, nose, mouth, (how the dog treats the game), temperament, marking ability, trainability, brains, drive, desire. All, items which have had no influence, or testing in the breeding of the CH dog, yet are absolutely fundamental in a Field bred dog. The physical appearance of the Field Bred dog, by breeding first and foremost for performance, has resulted in a dog which is longer than taller, has shorter ears, has a higher ear set, has a shorter stop, has no haw in the eyes. All these items have proven to be attributes in the field.