Showers are actually a symptom, and frequent showering is supposedly required (clinically) in order to be diagnosed with the syndrome. Without the frequent showering, the illness could be a number of different things like "cyclical vomitting syndrome".
Showers "help" with the pain and discomfort only while the person is actually IN the shower. Hence, frequent showering. The hot water dialates the vascular system which has something to do with relieving the yucky symptoms.
My son has not completely quit, but he's cut back -- and we are keeping a detailed journal now of when he smokes, and why. Again, this is medicinal smoking and not social. He has autism, a brain injury, a SEVERE anxiety disorder (primary reason for smoking), and is physically disabled. The number of prescription medications this kid was once on -- and the horrible side effects of them -- was outrageous. I hate that he is going to have to find something to replace medicinal weed because, for the most part, it really has helped him.