Does it mean anything to diagnose fibromyalgia (FM) in somebody with chronic widespread pain?

Looking at Fibromyalgia Differently – An Observational Study of the Meaning and Consequences of Fibromyalgia as a Dimensional Disorder

“…Fibromyalgia experts may also explain diagnosis by saying, "The diagnostic gold standard for fibromyalgia will continue to be the rheumatologist's expert opinion … [which is] the only way to capture the variability and severity of interrelated symptoms as they play out over time [45]." But rheumatologists are also uncertain about diagnosis [58][59][60], most diagnoses are made by primary care physicians, and there is no evidence to support or to contradict the validity of continued, updated diagnoses by specialists.…”