"Yeah, they did! For others." Rose laughs and shakes her head. "See? It's confusing." A quiet hum. "Okay. So let's say all worlds are like dots on a line, yeah? And they all exist spread out on a map like this." She uses all ten fingers to pepper the air. "And they move forward on their timelines in a straight line." She draws one finger from left to right in a line. "Well, to go from one world or another, he just skips the distance. And in the process of skipping that distance, it kind of scrunches the time down too. So normally if he's going to the same world, you'd think it'd be forward from the last time he was there, but not always. Sometimes the scrunch is a lot. Sorry, I know this is all kind of weird. Don't worry about it too much. It basically means... it's really difficult to get it exactly right. That's the price of easy world travel."