Cycling locals in Amsterdam are far from 'responsible'. People cross with red lights constantly, to the point where there is a social pressure to conform or be seen as either a tourist or just annoyingly in the way. People actively scare pedestrians by passing them close by and at high speeds (I've done this in... lesser moods, and I'm not proud of it).

The reason this causes relatively few accidents is because people driving cars in cities are extra careful.

Because of this I'm inclined to believe that the safety of cyclists is a result of regulation much more than 'responsible' cycling.