Interesting study. Here's some suggestions for further work (I'm always quick to take advantage of those suffering from OCD!
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1) use some 1"x1/8" bar stock pieces about 2" long, driven endwise into a scrap of pine. Apply the lube with a lubed patch, just as you would a barrel or slide.
2) instead of a salt spray test, how about a condensation test. Take the pine block and run it thru some freezer/no-freezer cycles to generate atmospheric condensation on it.
3) instead of salt spray, try mixing some plain old topsoil in the spray water. Maybe there are elements in dirt that accelerate rust, or maybe dirt particles accelerate condensation...