Tosh wrote:ESP has been developed with the average motorist in mind, one with no concept of handling or skid control. In order for ESP to kick in and do its job all you have to do is point the car in the direction you need to go. Hitting the brakes or accelerator will have no effect to the stability as the ESP will take over and maintain the car on the steering course you want. Using conventional skid control techniques of reducing steering angle in an understeer slide or opposite lock to correct a rear wheel slide will actually prevent the ESP from activating as it will not detect a slide.
If you watch Mark Kendrick's Bespoke Driving DVD, High Performance Roadcraft, he has a section detailing this information.
The OP's original question is a very good one. And the answer from my perspective is that it very much depends on the system in the car. I've quoted the post above because I think it is sensible answer that would apply to many systems fitted to modern cars. But I don't think it is entirely correct for all types of situation.
Specifically, in the oversteering example, ESP systems in performance cars are now, in many cases, tuned to allow a degree of slip and work with a driver who is countersteering, In fact, some systems are so clever that they
anticipate the grip level by matching what the sensors are recording against pre-programmed maps (e.g. Ferrari F12 as per its handbook). They modulate the engine's torque and electronic differentials (if fitted) to optimise traction and performance. In such cases, if the car begins to oversteer under power, the best thing is to "keep one's foot in", because the system will meter the power precisely for the available grip and allowed slip.
Clearly, I appreciate this does not apply to most everyday cars, but it will apply to a significant minority of performance cars on the road. Moral - best way to understand how to work with your car's systems is to have a play on a proving ground and experiment.
Cheers