I'm not so sure. When you contemplate the actual shape and configuration of what's missing, logic dictates that the part remaining in this strike *should* have been the part leaving first. It's the edges of a positive structure, and in this case the center has departed first, after the fashion of tooth decay requiring a filling. Pretty interesting, if you ask me.
Yeah, I was briefly thinking about that. The post must've just chipped at its center instead of being fully broken off