If you're playing a lot of Mario Kart 7 you are probably aware of a glitch on the Wuhu Mountain Loop course that allows you to shave 20 or so seconds off your lap time as you go off course in a specific spot. Nintendo are aware of the glitch, but don't plan on doing anything about it.
"We are aware that it is possible to navigate a certain part of the track in Wuhu Island in a way that allows a large part of the course to be bypassed," Nintendo's Buddy Roemer told Sticktwiddlers.
"There are no plans to update the game to remove this shortcut as doing so would create an unfair advantage for the users of the original release of the game."
If you're curious about what it looks like you can have a peek at this Youtube clip.