I tried baby oil once on my natural gut mains. It definitely softens them after they've become worn and frayed with use.
The problem with many oils is that they breakdown under pressure and heat, don't bond to surfaces, and collect friction inducing dirt and dust which defeats their purpose as a lube.
After this experiment I'm sticking (no pun intended) to simple low friction strings. Lubes just aren't worth it. I got more spin from a little extra mass than from these lubes.
On a scary note, you should see the recommended uses for the PFTE spray: the can lists stuff like bicycle chains, kitchen appliances, kitchen drawers, etc...
We live in a perpetual cloud of toxins intended to make our clothing, furniture, rugs, and drapes flame ******ant, stain resistant, and water proof. And we ingest lots of chemicals and toxins in our foods. And we have folks in our government who think it's just fine to turn well water into flammable chemical soup in the interests of drilling for shale oil (and voters elected those idiots!)
A little PFTE on strings probably doesn't matter in this context. But, why bother when the benefits are so tiny.
Pure Storm GT: 337g, 8.5 HL, SW 330
VS Touch Black/Focus Hex 1.23 @ 58/54