You know I was thinking about this center rotation point thing again alot while I was in the shower, I don't know why, I just was......anyways, to understand let me give you this visualization....... Imagine yourself from a birds eye view looking straight down at a car as it comes to the turn, it's a right hand turn, the car will understeer and respond slowly to the steering inputs due to the front tires being overloaded by turning the wheel too sharply, as the car slows down and begins to grip it will neutralize the understeer untill the car beins to go sideways due to a literall case of oversteer, then the driver will balance the car out and make the mistake of letting the rears suddenly regain traction sending the car into a spin to the left coming to a stop in the other lane facing the opposite direction.
Now think of how the car was rotating during all of this. The car will rotate at the EXACT MIDDLE as the car is understeering and even when it gets to a complete neutral state, will still be rotating in the exact center betwen the front and rear wheels. HOWEVER, once the car begins to oversteer the point of rotation will quickly make it's way forward. A tiny bit loose will have the point of rotation 3/4 of the way between the front and rear wheels toward the front. This is where the car is cornering the best, just a shade loose, anyways, the point of rotation will quickly make it's way to the exact front of car between the front wheels and will stay their as the car is drifting, however once the mistake of overcorrecting has occoured the point of rotation quickly moves to the rear of the car untill the front wheels grab more than the rears again and the car starts sliding the other way, moving the point of rotation to the front of the car again untill it stops.....then, obviously there is no point anymore.
This has 100% to do with the position and direction of the momentum of the car and that has alot to do with the grip levels at each tire. Momentum is created by grip level indifferences and grip level indifferences are created by momentum. All of this is very dynamic.
GT4 Does this all perfectly, As does EPR, all of the codemasters games fail miserably, this is why they float, this is why they have glitches and unrealistic things happen in them.