I will confess that I never properly understood how the rebooting of the universe in the Series 5 finale worked, exactly, but wasn't it the case that the timeline with the collapsing universe was erased? Ergo, Team TARDIS are really the only ones who remember things like Rory being a plastic Roman? So why did Amy tell baby Melody that her father, better known as the Last Centurion, would be coming for her? She couldn't have known that the Doctor was making him dress up, and there is no reason to assume anyone remembers the legend after the universe was rebooted. Right?