Under the multiverse theory, going back in time would just have split the timelines into two at that point. DBZ explains it well, that's one educational show
So If I kidnap now a Sheep-Cutie, then travel one hour back with her, and then kidnap the the same Sheep-Cutie one hour earlier, and then travel with them back another hour, and then again kidnap third Sheep-Cutie, and then again go back one hour with my all three sheep cuties.... and kidnap fourth one..... ETC, I'd be able to collect THE ENTIRE GLADE OF THE SAME SHEEP-CUTIES?!
And then we'll rewrite Irrlicht! The team: myself and 1000 Sheep-Cuties!
(yea I know I'm more skilled than even one thousand of thems!)
It would be so coool as a woool! Someone plx invent a Time Machine, as I much desire to clone Sheeps!