It took nearly 100 years for the impressively effective intervention of using forceps in troubled childbirth to become public knowledge, according to Gawande...Peter Chamberlen, the obstetrician who invented them, kept them a family secret for that long. It's an interesting illustration of what happens when there's no way to profit from an invention. N.B. I'm not only referring to the patent system here; there was likely no renowned academic job to be had for disseminating the invention widely either, given that it was the early 1600's.

Ari