I looked up the paper and it is evident that they don't consider having a clear diagnosis to be a benefit to the patient. That is a obvious nonsense, as can be easily appreciated when you turn it round and ask the question: What is the effect on a patient of having a painful condition and not being given a diagnosis?

The answers are in the posts above, and I have also experienced them. In my early stages and again as my condition progressed, the attitude of Doctors led me to suppose they thought me a fraud, and that attitude eventually allowed my own condition to deteriorate to the point of an emergency operation for spinal decompression. (I don't have peripheral neuropathy, it is my spinal cord which is damaged and gives me neuropathic pain, but hey I'm splitting hairs, the principle is the same: Non diagnosis is harmful.)