You know, Snakes DO actually produce oil...all this Snake Oil stuff is a Red Herring.
Before they shed their skin (actually, top layer of scales), they produce an oil underneath that helps loosen the scales....You can tell, as their skin dulls and their eyes (which are covered by a scale) turn a milky blue colour, as the oil collects between the eye and the scale, known as "in blue".
What works? Being able to see properly...any doubt about your vision should be a priority.
Then I and other people find that a purple lens, helps bring out the clay, in sporting environments...very much so.