If you are going to invoke the concept of folklore, you should know that the contemporary study of folklore includes the folklore of corporate business, the folklfore of science, etc. Some people prefer to call these contemporary forms of folklore 'urban legend' or 'urban myth'. Scientists and other linear rationalist thinker types are in no way immune to creating, believing, and perpetuating their own folklore.

BTW, I was diagnosed with a duodenal ulcer (had the wretched scope test and everything). The biopsy (or whatever they call cutting off a piece of the ulcer to test it) didn't show even a trace of h. pylori in my case. But they treated me with extremely powerful antibiotics and acid suppressant "just to be safe". A perfect example of the medical industry's adherence to the current 'folk cure' on offer for duodenal ulcer, IMO.