The expanded, general-purpose version of Greatrakes’s claim underlying his 1666 English celebrity. It rests on patient self-report and testimonial letters collected by Greatrakes and his allies, with no controlled comparison or independent diagnostic confirmation, and no systematic clinical test of the claim across the named conditions is documented in the sources reviewed for this case. Individual documented attempts failed: weeks of repeated stroking applied to Anne, Viscountess Conway’s severe chronic headache at Ragley Castle in early 1666, in the presence of prominent witnesses, did not work — the Dictionary of National Biography records that Greatrakes “exerted his art upon her in vain.” A formal demonstration before Charles II and the royal court in London later that year likewise failed to persuade. The Dictionary of National Biography’s own account further notes that his failures in some cases, “not apparently more hopeless than others in which he had been successful, could not be explained satisfactorily” — i.e. the claim could not account for its own inconsistent results.