That SMB3 video is a fake. If you play it at the same time as you play the game, he's running way faster than is actually possible in the game. I've tried it. He slowed it down to cheat his way through it, and when he sped it back up he sped it up a little too much. The guy who made the video admits this all too, but it's in Japanese, so it still pops up on the internet every few years with people thinking it's a legitimate speedrun. It's still amazing to watch, but it must be noted that it's in the "superhuman impossible cheating" category.












