When a computer can read that the tire just crossed a small puddle of ice on the highway due to micro slip one thousand times a second, and begins to adjust for ice conditions... how are we still wondering if the "human factor" wouldn't throw a wrench into the equation faster than that?  Huh.  By the way, that computational reference was from Elon responding to someone who asked if full autonomy adjustments would process more quickly than a human brain/body could interpret and execute corrections behind the wheel.  Further, people cannot "see" half the things a computers' sensor can "see," such as a small black ice puddle.  I understand Lex is saying humans interpret the world around them while driving much differently than software - but a computational system simply reacts to factual occurrences much, much faster.