I'm going to argue the planets he busted weren't earth sized, they were the size of Kepler-10c, which is about 17 times earth mass. Prove they weren't!
This definition, which applies only to the Solar System, states that a planet is a body that orbits the Sun, is massive enough for its own gravity to make it round, and has "cleared its neighbourhood" of smaller objects around its orbit.
So Kepler-10c is nearly 20 times the mass of earth, and Mercy is about 1/20 the size of the earth. 'Planet' busting seems like there is a wide range anyway.
These are just rocky planets which it looked like to me are what Bill busted.