By rotation I meant vertical rotation from front view to back view. If you tilt your head to right, and then rotate your body 180 degrees on its vertical axis, your head will still be tilted to it's right. But if you rotate only your head 180 degrees on its own tilted axis it will end up tilted to it's left, not right.
But you are right , no matter the axis of rotation, when you face backwards and then tilt your head, the view tilts the wrong way. And it happens in trackIR itself, no matter which game title you select. And you can see that if you turn 90 degrees to left or right, tilting your head does not tilt the view. I mean 90 degrees in TrackIR.