I had been having issues keeping my 5 string bass in tune and would often have a lot of minor tuning adjustments to do prior to each session.
I decided to use this on the nut slots, bridge saddles and through body ferrules when I changed the strings. I now note that my bass remains in tune between sessions. I use a strobe tuner for tuning purposes so it's easy to see the pitch accuracy of each string and they are now always perfect and adjustments are less frequent.
Granted the string set may also be contributing to the stability, however, I feel that the lube in the nut slots is likely an essential part of the improvements since there is now no string binding with the nut material (bone, in my case).
My conclusion is that this a simple and effective way to improve tuning stability, definitely would recommend it.