As applying an oil layer on iron before starting any cleaning process has always been the basis of my philosophy, your suggestion sounds fair enough.
I prefer olive oil as it has been a) the historic oil care since at least the invention of firearms some 700 years ago, and b) in my experience provides the thickest and most consistent lubric layer.
Anyway, I would be eager to learn how you define 'patina' compared to 'rust'?
In other words: on what criteria is your method based?
And: why remove patina at all?!