Breed type is much more subtle and much more complicated than what can be defined by words alone.
One of my favorite sources on the subject of breed type is a book written by Richard Beauchamp entitled Solving the Mysteries of Breed Type. In his book Mr. Beauchamp examines many breeds and discusses qualities of type that are important for each breed. He gives the reader an appreciation of how diverse the dog species is ... and how difficult it is to describe breed type in words.
After considering these many breeds and identifying their defining qualities, Mr. Beauchamp concludes that there are five elements that determine breed type. Those elements are:
Silhouette
Head
Gait
Coat
Breed character
I believe Mr. Beauchamp is spot-on in defining the components that constitute breed type as it applies to Dobermans as in other breeds.
First let's look at Silhouette.
The visual outline of a dog is the major way we identify a breed. You should be able to see a dog at a distance and be able to identify the breed by outline alone.
The silhouette conveys much about breed type; size, proportion, substance, angulation, topline, underline, tailset, head carriage, along with a myriad of other traits. All of these traits must combine in a unique way to become that breed, and to be unlike any other breed.
You can describe a dog until you exhaust your vocabulary, and still not have a person visualize a breed that he has never seen before. But show a live dog or a photo of a correct Doberman, and that person has an immediate appreciation for how the breed should look.
Since outline or silhouette is decidedly a mark of breed type, it is important to have an image of the breed in mind to determine breed type.
Below are photos of very good male and female Dobermans. These images should be so affixed in your mind that you can very quickly compare a Doberman standing before you to the mental image of the ideal.
You can see from these images the compactness, the correct head proportion, the proper neck that flows smoothly into the 90º front angulation. You will observe the solid slightly sloping topline ending in a 2 o'clock tailset with a moderate underline and with rear angulation that matches the front. With the silhouette, you will see the strong substance, cat tight feet and athleticism.
Once you have the ideal silhouette committed to memory, and after observing many representatives of the breed, you will be armed with the tools to help you identify that element of breed type.
Now let's look at heads
Just as you should be able to identify a breed by profile alone, you should be able to identify the breed of any dog when only the head is visible.
Though the description of our head is similar to other breeds, the Doberman head does not look like any other breed. Many breeds ask for parallel planes, blunt wedge, dark eyes, and high ear set, but they are not even close to resembling a Doberman.
Dobermans have a dry head with a flat skull, smooth planes on the side of the head, erect ears and a vigorous and energetic expression. The head should give the impression of planes, not curves, and intensity, not softness.
The standard's wording of a blunt wedge is not an exact measurement. A blunt wedge can vary from very wide (think Rottweiler) to very narrow (think Collie).
A heavy-bodied Doberman will likely have a wider angle to the blunt wedge, whereas a narrower skull may be more appropriate on a dog with lesser substance. Both could be acceptable as long as the head fits the rest of the dog.
You must know the limits of the wedge that are correct for a Doberman. You can do this by having the image of the ideal head stored in your mind's eye for reference.
Of major importance of the head is a full muzzle with a full complement of teeth. The Doberman was bred as a personal protection dog. To protect against threats, a Doberman needs the strength of head to manage a full sized man that threatens the dog or his owner.
The standard calls for a disqualification for dogs with four or more missing teeth, or overshot more than 3/16ths of an inch, or undershot more than 1/8ths of an inch. The most frequently missing, and easiest to find teeth are the pre-molars. Missing teeth can occur at any part of the mouth, incisors, pre-molars, or molars (usually the rear-most molar). It is imperative to check all teeth for proper dentition.
Extra pre-molars are quite common in the breed. The standard calls for 42 correctly placed teeth. More teeth is not better. More actually represents two faults. First is that there are more than the 42 specified by the standard, and second the teeth cannot be correctly placed if there are too many of them.
Having said all of that, a missing or extra tooth is incorrect, but a dog should not be excluded from consideration for this singular fault.
Another consideration in the mouth is the occlusion. Occlusion is best examined with by examining the bite, then lifting the lips to reveal the upper and lower premolars. These premolars should fit such that the they mesh symmetrically between each other as shown here.
Correct Occlusion
A good understanding of the correct head will lead you to become a better Doberman judge or breeder.
The next element of breed type is gait.
Each breed has distinct gait, but there are many common factors of the gait that are typical of many breeds.
Dobermans tend to have a strong, powerful gait, yet with light footed action. They tend to have wider strides than many breeds. As an example, some herding breeds call for similar structure in their standard with strong reach and drive, but in comparison they have a more moderate gait than a Doberman.
When observing the "running gear," the essential characteristics for Doberman side gait movement are correct reach and drive, interchange of the feet under the dog, and feet close to the ground.
The reach and drive should be balanced with the front foot reaching near the nose and the rear drive extending in a like angle and with the hock joint fully open and the rear pastern fully extended. The exchange under the dog should be with the back foot stepping into or near the exiting front foot.
In addition the dog must maintain a look that is very similar to the dog when he is in a stacked pose including topline, underline, with slightly forward head carriage, and tail carriage as shown below.
Correct Side Gait
The figures below show the correct movement for the down and back for a Doberman. Notice that the front leg forms a straight-line column and moves in the same plane as the rear leg on the same side. The legs converge toward a centerline under the dog.
Correct Front and Rear Movement
"Which is more important, the side gait or the down and back?" The answer is "both." The characteristics that are important in side gait are not observable in the down and back. Conversely, the characteristics of correct movement in the down and back are not observable in the side gait. Even though you can see more characteristics in the side gait, the down and back is equally important. Both must be observed to find a sound dog.
The fourth element of breed type is the coat.
The dog world is teeming with different types, textures, lengths, and colors of coats. It is clearly one of the most important components in breed type.
This element is the easiest to understand in the Doberman. It has no unusual characteristics, but it's coat does help define the breed.
The Doberman coat is a short, hard, shiny coat, with little or no undercoat. If undercoat exists, it will typically be in the neck area. The coat should always be hard. There are coats that are soft, smooth, and shiny. They can be very attractive, but they are not correct.
There are four colors, black, red, fawn, and blue, all with tan or rust markings. The only allowed white is a small patch on the chest measuring no more than 1/2 inch square. Any other color is a disqualification.
The final element that defines breed type is breed character.
The elements of breed type discussed above deal with the physical appearance of the breed. That's all that has been described and many people would stop here, but those elements don't tell the whole story. The breed must present the proper character for its breed.
The AKC Glossary of Terms defines character as "Expression, individuality, and general appearance and deportment as considered typical of a breed."
Harold Spiro's book Canine Terminology limits his definition towards temperament and defines character as "Dogs mentally equipped to perform those functions for which they were originally designed are referred to as being 'true in character' for that particular breed."
The Doberman is a regal breed with the distinctive combination of being elegant while still maintaining strong substance. It should be a compact, athletic, confident dog that presents himself as aware of his surroundings and in total control.
The standard has descriptive phrases (Elegant in appearance, of proud carriage, reflecting great nobility and temperament. Energetic, watchful, determined, alert, fearless, loyal and obedient.) They all are important.
Since the Doberman was bred as a personal protection dog, he should exhibit the traits of a animal that can perform those duties ... quick, powerful, determined, confident, and controllable.
The athleticism, stature, and presence of a confident Doberman draws attention from everyone, irrespective of their breed of choice. Observe a good Doberman returning from moving and hitting that perfect stack with the look of "I'm here, and I'm in command." Could that be one of the reasons that Dobermans are so successful in group competition? If you have watched a number of strong working groups, you've seen it. When you see it you will know "that's a Doberman!"
Thoughts about crop and dock
A docked tail is clearly defined the standard. There should be no other acceptable tail.
A dog with uncropped ears deviates from the standard in three specific instances.
It is not cropped.
The ears are not carried erect.
The standard states that the Doberman look is "determined, alert, fearless, loyal and obedient." Natural ears on this breed have a much softer and less daunting look than the erect ears of a cropped Doberman. A soft look is counter to the appearance desired in our breed. This is a third and important deviation.
One should be able to identify a breed solely by its silhouette. The Doberman silhouette cannot be identified as correct breed type if it has natural ears and an undocked tail
Conclusion
If you thoroughly learn the first four elements of breed type and have those mental images in your mind, your will be able to choose the physically correct Doberman. The final and arguably the most important factor that you will evaluate is breed character. Choose carefully, breeders and judges. You control the future of the breed.