The simulation found that there was a "strong" correlation in elements between the Earth and a Moon made out of its material, but that the same wasn't true for a Moon made out of the Mars-scale body. There's an explanation for those remaining five elements, too. They have substantially lower concentrations in the simulation, leading researchers to theorize that the elements didn't re-condense after the impact and separated from the material that would become the Moon.

You won't want to toss out your existing knowledge just yet. There's more research necessary to understand the environment of the post-collision disk. This early work fills holes in scientific data that have existed since the 1970s, though, and it could serve as a launchpad for more research. If that work validates the early hypothesis, you might end up looking at the Moon in a very different light.