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Felt like explaining a little bit of the physics involved when driving in a corner.
When cornering on the limit, weight is distributed close to 50/50 front/rear, and all the grip is used for transverse acceleration. As you exit the corner, the driver starts feeding in power. The added forward acceleration will shift weight from the front to the rear wheels. That mens less grip up front, and more grip in the rear. This is the same for FWD, RWD and AWD cars.
In a rear wheel drive car, the aim is to use the extra grip in the back for forward traction, while still cornering at the limit with only transverse forces up front. The power you add, the more weight shift will happen, and then you can add more power again. Cars with short wheel base and high center of gravity has more weight shift than long and low cars.
With AWD (and FWD) cars, it is impossible to add power without using less front wheel grip for transverse forces. That means you get understeer and a wider line once you start using the throttle in a corner. Some grip is lost in the front due to weight transfer, and even more because you are using it for forward traction.
In low grip (slippery) conditions, there is a lot less weight shift to the rear wheels. If you still want to use a lot of power out of the corners, there will not be much left for transverse forces in a RWD car. You need to straighten the line a lot. With AWD you can get the same power down with only half the traction forces in the rear, so you can corner tighter.
Basically this means that a car should have pretty much 100 percent of the driven forces on the rear wheels in high grip conditions, and then gradually less the more slippery it gets. Having more than 50 percent of the traction on the front wheels does not make much sense, unless the car is designed to have a very front biased weight distribution.
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