Just a little! Apply around the joint with end of a round toothpick? Vinegar can work on corrosion too, sometimes.
Not sure if naptha would do anything, but similar to alcohol it would eventually evaporate away (but can leave residue). Oil has the slight possibility of migrating somewhere you don't want it. Perhaps light machine oil: I'd reccomend very sparingly. Sonnar Brian has certainly dealt with some "sticky" repairs (as I've learned, reading his experiences here at RFF). If he reccomends alcohol, I'd do that.