Italians...

...(and the French) actually obey that unwritten rule of the road where from left lanes to right lanes your speed is fast to slow. In fact, it's not unwritten here: it's posted what your speed should be in each lane. There are signs showing all three lanes marked with a speed in km/hr, and even if you're trying to pass on the left, if a car behind you seems to be going faster, most people will move back into their travel lane to let others speed by.