You "normals" always claim that "Inverters" should also invert the x-axis because of this mistake, and that mistake is shown in this image on the wiki.
The mistake is entirely with the visual of placing the stick on the back of the head. You should instead view your entire head as the analog stick. Are you doing that? Good. Now with your head as the stick you still look up when pulling the stick back and still look down when you push the stick forward. However, when you push the stick to the side, the head does not turn, it leans. In the case of aircraft, where I am sure a good number of us "Inverters" learned this control scheme, the aircraft banks to that side.
Now, when you lean your head to the side, your body tends to follow your head and turn that direction, in essence it is banking to the direction your head is leaning as an aircraft would bank to the direction you are pulling the flight stick.
This becomes even more apparent when you view your entire upper body as the analog stick, when you bend/lean your upper body, the rest of your body will go to the direction that you are leaning.
I have yet to figure out how you "normals" justify that scheme when you aren't moving a crosshair around the screen and it is instead staying in the center of the screen.
One final thought: When and why did inverted controls get named inverted? I distinctly remember them being normal when I was growing up, though my memory may be flawed.