Well, I understandt that there is a quite clear difference between a planet, a dwarf planet and "other objects". There are some known objects that have not a clear classification yet but anyhow.
If you think that electromagnetism has something to do with Astrology, as I do, you can easily notice that a planet in a clear orbit should be much more influential than a dwarf planet in a "soup" of many other objects that would distort the signal just as aluminium threads may confuse a radar (all the rest being equal).
Simlarly the distinction between a "perfect" round object and an "imperfect" irregular rock, which is by IAU 2006 the line between dwarf planets and simple asteroids/KBOs/other, should make a difference. We obviously would need to know more about the distant objects' magentic fields and how they affect the Solar magnetic field but I understand these physical distinctions may make a difference in any case.