Not to drag another tragedy into this thread, but the recent Air France Airbus 330 crash seems to dispute the statement about a computer's ability to do it better or more reliably than humans. Computers are programmed by humans and take input from sensors. Humans and sensors both can fail, so there is always a chance of error.
The monorail accident is a horrible tragedy and my heart and prayers go out to the family of the pilot. The more I read about how this happened, the more it appears that this could have been easily avoided if people (yeah, the humans) were paying more attention to what they were doing.