Actually not the case...

Unless you use light coats wet on wet.... Oil cannot penetrate itself once it's dried... it used to before the VOC laws came into effect but now they've taken everything good out of oil. (soon you won;t be able to get oil paints)... The preffered system for house paint in oil primer latex top. And Epoxy is NOT oil based. As for plugs..... as HABS says do your homework.

-Dave