The idea is to create an "in race random event" where drivers can commit mistakes and lose time.
From a programming POV, there could be several alternative "racing lines" in each track, like the boxes in every track, and a chance, depending on the driver ability and wheather he/she is battling other driver and so is under preassure, that the driver goes of the track and so losses some seconds.
For the moment I think the only driver mistake we can see is drivers locking up, but they seem to not lose time at all.
Thanks.