It changes how much the wheel turns, but it's subtle / intuitive so you don't notice it's there. Unless you drive the same kind of car without the option, then you notice the steering seems not as nice.
It is also used by stability control to counter-steer small amounts of oversteer. But it can only do so for a relatively small amount of wheel angle change, not turn the wheel 90 degrees or something like that.
It is also used by stability control to counter-steer small amounts of oversteer. But it can only do so for a relatively small amount of wheel angle change, not turn the wheel 90 degrees or something like that.