Even deeper study on the subject has now shed more light on the subject for me, clarifying what a Navajo I once met meant when he told me that "us Skinwalkers prefer the term 'spirit walker.'" At the time I thought he was just trying to be contrary and to show that I didn't know much as a white person. The more I have dug, the more I have seen why some Skinwalkers would want to be referred to as spirit walkers.
Some Skinwalkers will perform their work in spirit form, instead of just in a physical form more or less resembling the animal whose skin they wear. This spirit form will allow a walker to perform task he would normally not have the ability to perform, even wearing an animal skin. The walker will make spiritual objects mean to harm others, which vary in form and function.
A person may not detect the presence of a spiritual walker as easily, and will also need to deal with the walker on the spiritual plane. This means physical blocks such as locks, security systems and even weapons will be ineffective against a walker in spiritual form. The walker has left his body behind and so has gained capabilities he would not have in his body.
This viewpoint of the Skinwalker as a spirit walker will challenge some people's way of thinking since the concept is so much more abstract than a guy who dresses in a wolf skin and becomes a "werewolf." Stepping out of one's ethnocentric circle comes with vast rewards as you are able to see the world from a different viewpoint, and begin to develop the ability to see the same thing from various viewpoints. I would argue that for anyone who wants to study the paranormal on a serious level, such an ability is absolutely essential.