As far as I can tell, many planetary scientists aren't particularly fond of the definition either. I believe the initial plan that the IAU had after the discove

As far as I can tell, many planetary scientists aren't particularly fond of the definition either. I believe the initial plan that the IAU had after the discovery of Eris was to classify dwarf planets as planets, but some of the members didn't like the idea that our solar system would suddenly get a lot more planets, so pushed for the current awkward and ill-defined IAU definition. Though there are a lot of people that present the IAU definition as if it were simply the will of "science," if you look at the 2006 debate about it amongst scientists, it was actually fairly contentious.