"You clearly have no clue about Amsterdam."

I've ridden all over Amsterdam and most of the Netherlands over a period of years and it's a great place to be a cyclist, at least in the warmer months. My point, although not well stated, was made for the benefit of those who try to make commuting so complicated here. Nevertheless, I don't think carrying an open umbrella on a bike is going to catch on. The fellow in question rode past the van Gogh museum one morning while we were standing in line to enter. He wove out of sight down the street waving that umbrella in the breeze.