Believability is limited in realism. I'll give a simple example. Kenshin from Rurouni is capable of using his God-Speed battoujutsu techniques, something that surpasses the sound barrier to nearly light speed levels. A normal human would never be able to achieve this level of speed without an immense amount of strength that could result in planetary destruction. But Kenshin is not that strong. He's skilled. It's a fantasy based skill that he utilizes. There is some very minute logic implemented into it, but otherwise don't think too much into it. I'm from a much older generation that doesn't care so much about the sciences, so long as it -can- make sense. Which I, of course, believe it does. I'm not attacking you. I am explaining as you asked :o Also, I know I've been dramatic, but I want to spice things up and hype what my students and I are doing. It'd be nice to have more people like LeeRoy getting into it. Ya'll should lighten up.