Primary sources, a historians best friend. And, maybe, just maybe, also best friend of the coach and athlete. Do we have an information problem or to do we have an interpretation problem? We present a specific explanation of the mechanism that's behind the concept of lactate threshold, we give historical evidence for it's application by it's most famous, and overwhelmingly misunderstood, proponent who probably never called it lactate threshold. Is there a moral to the story? Maybe it's that it knowing stuff, even if it's science, is pretty important. Strap on your aquatic lung, we submerge into the archives, diving for wisdom's lost pearls.