Narrow gauge isn't the issue. It is the extremely treacherous gradient and curvature that can bring even experienced drivers to grief if they lose focus even for a second. That track would be just as tricky if it was standard or broad gauge. Trying to stay focussed in the dark, early hours of the morning, on one's own (D.O.O.), tired, near the end of a long 12 shift can test the best. I admire all those drivers that, most of the time, safely negotiate that and similar track on the mainland, with heavy trains in often appalling conditions, fog, sheeting rain, dodgy locos, tricky brakes, unpredictable rosters and long exhausting shifts. To say they don't get paid enough is an understatement!