I found out I work with an ENFP, I tried to convince her she was ENFJ (she typed enfp on an online test), I even had people tell me there was no WAY we were the same personality type. I later realized I was just being selfish with my type (after she typed enfp on another online test I had to admit it to myself), she thinks the same way as me and has the same struggles, even if we don't manifest it the same way. We've also matured in different ways and have had very different lives which highlighted different strengths in our personality.
I think that many people can probably fit a few types fairly well, not all of our preferences are 100%. I think "x" is an appropriate way of dealing with fitting two types or needing uniqueness.