its called PMI.

Polar Moment of Inertia.

Given that the 'mass' of a MR vehicle is closer to the center of the car, unlike a RF or RR, i makes the car harder to rotate around the center axis of the car. Think of spinning a stick with a 1 lb weight at the center like a propeller. Now put 1/2 lb at the far ends of the same stick and spin it....

It just makes the on-the-limit driving much more twitchy then a FR car. It can be done, but the factors involved for drifting are hard to apply to that drive train layout.