Then you would adjust the idle-stop/speed screw so that there is a 1-2 mm gap when the servo is in the neutral position. You might need to readjust the spring collars on the throttle linkage to force the throttle arm against the idle speed screw.
An illusion is a distortion of perception. The brain arranges, sorts, and organises data from the senses. Normally the system works well. Sometimes it does not, and we see illusions. In general, they are shared by most people in the same situation.
A cognitive illusion can be defined as the viewer's knowledge and assumptions about the world, or unconscious inferences. There are three categories of cognitive illusions: ambiguous illusions, distorting illusions, and paradox, or fiction, illusions. Ambiguous illusions are images or objects that allow for the viewer to have two valid interpretations of what the object represents or what it actually is. The viewer is usually able to mentally visualize one interpretation right away and eventually the second, after some time.