As much as I understand, the type shows what people actually PREFER to use and I'm pretty sure this won't change (unless perhaps one already is borderline-something anyway). But it is possible to learn to handle the opposite functions and get quite comfortable at them. For example, I am extremely N, but I actually pay special attention to experience and grow S. So I could 'switch it on' when needed... But never mind how good I might get at S, I'm sure I'll always PREFER to use N by default. Something like that.