I dont understand how you can generate missing information.....kinda like focusing the enlarger to remove out of focus, don't work... !!
IF I understand it, your camera shoots RAW, and records raw,[and makes jpg] or both as you select. true? if so the only reason not to save RAW is camera memory size... ?? BTW, I save both.....
why bother....while keeping the raw is not a bad idea of coarse, just make a copy of the jpeg, mess with the copy and go back to it for another if necessary.....