The long elliptical orbit stands in contradiction to human trajectory theories, which have a trajectory curve downward mirroring the trajectory curve upward. Repeating comets are going in an essentially straight line away from the Sun, a line parallel and very close to the one that would be drawn from the very center of the Sun. Human theories of such trajectories on Earth state that an object going in an essentially straight upward path returns from the same place, plunging straight downward with a curvature mirroring its upward path. In contradiction to this explanation, complacent humans find nothing strange when comets reenter the Solar System at a great distance from where they left. The explanations given by humans for this contradiction in their logic is the Magical Ellipse explanation. The ellipse needs no explanation, it just is. When asked to describe the forces that control an elliptical path, humans proffer a technical description of an ellipse. They describe it, not explain it.
The long elliptical orbit stands in contradiction to human gravitational theories, which has the gravitational tug rapidly diminishing with distance. Where the temporary orbit around the Sun has an explanation in the steady gravity tug from the Sun, this same explanation is given for the curve they claim is instituted by the repeating comet at a great distance. Essentially, humans refuse to even address this contradiction, falling again into the Magical Ellipse explanation. Their response, like the cat which falls to licking itself when it is discombobulated, is to proffer greater and greater detail on the math they use to draw or describe an ellipse.
Comets, whether termed repeating or non-repeating by humans, assume, however temporarily, an orbit around the Sun. In this they are going the fastest when going into this curve, and are going slower when they leave off from the Sun.