In Flight mode of a ship, moving the mouse the same physical distance results in different facing directions at the end of the rotation if one of the mouse movements was faster than the turn speed enough to send the circular cursor off the side of the screen. In other words, the game appears to not accurately track mouse movement past the edge of the game window.
For example, with mouse acceleration disabled, moving the mouse 2 inches to the left at a rate of 2 inches per second, causing the cursor to fly well off-screen, will rotate the ship 45 degrees counterclockwise along the XY Plane. Again, moving the mouse 2 inches to the left, but at a rate of 0.5 inches per second keeping the cursor well inside the window, will rotate the ship 180 degrees counterclockwise along the XY plane.
This results in much more distance of mouse movement required to turn a set angle if the mouse is moved too quickly. It is like reverse mouse-acceleration/enhance-pointer-precision. This is detrimental to player health as repeated, high-speed flicks of the mouse escalate wrist muscle deterioration. This is also detrimental to player skill growth in competitive aspects (both racing and combat) because muscle memory cannot develop accurately.
I have tested and seen this issue affecting fullscreen mode, borderless fullscreen mode, and windowed mode of various resolutions.