Hey thanks for posting this link!
Really interesting to hear the Dutch perspective. I worked in Rotterdam for a while and rode all over the city as well as to Delft, Amsterdam and The Hague on some pretty extraordinary infrastructure. Yeah, the Dutch don't ride all that fast. They often looked at me like I was crazy for moving at the pace i was. Part of it is they don't wear cycling specific clothing so they don't want to work up much more of a sweat than they might at a fast walk- makes sense. But some of the Dutch do ride substantial distances on their commutes- easily measured in kilometers not meters but again at a moderate pace. I seldom saw anyone wearing a helmet. In fact, I, who wear a helmet consistently when I ride here in the US, rode without a helmet. I seldom wear cycling specific clothing, other than my Austin Keen's on my commutes so that was not much of a departure.
I ran into some Dutch cyclists in Boston one summer and they were touring the city on rental bikes. I was surprised they were wearing helmets and asked if they wore them at home. Their response was, "We don't need them in the Netherlands but riding in America is terrifying." Oddly enough on a ride to Delft I saw a female cyclist get hit by a van as she crossed a small cobblestoned bridge. She was side swiped at a very slow pace and hit her head hard on the stones. She was knocked unconscious.
The Dutch were amazingly efficient. An ambulance arrived in minutes. The driver was arrested, the scene photographed, the bike taken away in a police van and the cobblestones hosed down and everything returned to bliss within a half hour.