Haydn. You need a correction here. The outside wheel turns a greater distance than the inside wheel, and it doesn't turn backwards. It is still going the same direction as the inside wheel. A locking differential prevents this and both wheels turn at the same speed. This is perfect for drag racing. But even in road or oval racing it can work too as it will help induce oversteer. And if one wheel comes off the ground that side will "unload" as all the power will go to that wheel and not the wheel with the traction. That's where a "limited slip" differential will help. Or if it is locked that won't matter. But if it is a design called a "Torsen Differential" then the power will got to the side with the traction because it uses worm gears which can only rotate on direction and lock in the other so it won't unload.