I would hazard a guess that to provide some protection is that the system would would not permit real time update to existing road structure and using inertial

I would hazard a guess that to provide some protection is that the system would would not permit real time update to existing road structure and using inertial guidance would rule out any change to its location that would be impossible to achieve within a set time. So say you tell the car an exit it has been confirming for sometime is three miles, any change in that distance based on what the car knows it is doing should be enough to flag it and require intervention. Granted a lot of the article is one sided but the cars need to be smart enough to know where they should be relative to where satellite places them especially when that information changes to quickly to be valid. the problem of self driving is fascinating and it just goes to show there is always someone or something that will throw a wrench into the process