Isn't a certain degree of gumming-up advantageous? It would keep the oil in place after it works it's way into all the nooks and crannies, ending up more like a grease. This behaviour could be good for corrosion prevention.
Oxidized vegetable oil is the most disgustingly tacky substance that I know. It's like a cross between rubber, glue, and grease. It is very resistant to removal with "intuitive" methods (but using un-oxidized oil and heat tends to work) and it doesn't lubricate, it sticks. It can't possibly be good for lubrication, I'd say. Unless you can somehow control the process so that it oxidizes just a little.
That's not how vegetable oils gum, they go sticky in a way that's not like grease. Hard to explain but if you feel them both there's a huge difference. Grease will stick but isn't stick-y in the same way if that makes sense.