It's an interesting take and a nice challenge at the same time.
It feels like there's room for playing around with the speed of the run vs the speed of each of the player characters: it's difficult to truly react for both characters unless you set them each on opposite sides of the stage to let Joe blast across if he needs to or you do a quick dodge if there's something on your own side. If the dog were faster and the scroll of the level were slower then the game could turn into much more of a reaction steering game rather than a setup-and-side-swap type of experience. Either way honestly works, but it's worth bringing up in case that was or was not your intention for effective player behavior.