These scenarios can be solved by immediately triggering a remote driver to connect in and monitor the situation, or even switch to manual control.
Self-driving cars will never happen.
In certain contexts they exist already. You're arguing against something that already exists.
What's going to happen from here is that the context is going to become broader and broader over time.
As it always has.
This is how technology works.
"You would make a ship sail against the winds and currents by lighting a bonfire under her decks? I have no time for such nonsense." [1]
[1] http://www.goodreads.com/quotes/442305-you-would-make-a-ship...