The reason for traffic congestion and its resulting high blood pressure and foul language is that not everyone plays by the same rules. 
  What is second best to everyone driving under the same rules is not almost everybody following the rules. Second best is no rules at all. 
  Adherence to no rules is similar to everyone adhering to the same rules in that everyone knows what to expect. 
  In this country, it’s probably not possible to require competence beyond ability to read speed limit signs as prerequisite for a driver’s license. We all regard driving the same way many Americans regard owning firearms——a right not to be abridged or trifled with in any way. 
  If all drivers understood that the left lane is a passing lane to be yielded promptly to overtaking traffic, and if people on two-lane roads pulled over to let faster traffic go by, there’d be no pulsating, bumper-to-bumper, hub-to-hub, multilane, rolling traffic jams.  
  Where two lanes shrink to one and traffic has to merge into one lane, some drivers move into that lane as soon as they see the sign saying the other will end in a mile. To their minds, they’re being responsible and courteous. It also averts a confrontation when the two lanes finally do become one. It makes those drivers furious as they sit in slowed traffic while other drivers see nothing wrong with continuing in the other lane until it actually does end. 
  It’s the second way that works best and is most fair. If traffic merges before it has to into a lane that is moving slowly, who is to say what the proper distance is from the end of the lane? 
  Far better to use both lanes and then take turns merging like teeth of a zipper. But not everyone understands that, and people get mad. 
  While most American highway police forces concentrate on writing speeding tickets to finance state governments, Puerto Rican police finance their government by writing $50 parking tickets and leaving traffic alone. The result is scary at first. 
  Our taxi rides between airport and hotel in San Juan are a course in driver’s education not found in any U.S. classroom. Traffic appears to be anarchy at first, but then so does an anthill. What is really going on is vehicles moving quickly and efficiently. 
  Puerto Rican traffic offended what little sense of orderliness I have. 
  While most U.S. drivers tend to add a few mph to the posted speed, I don’t know why Puerto Rico puts up speed limit signs at all. 
  After a time, I began to appreciate the skill and attentiveness required of drivers. I began to notice how well traffic moves. Driving in Puerto Rico is not boring. 
  By the time I first rented a car to explore the island, I’d come to realize Puerto Ricans drive the way I probably would if I didn’t have to worry about radar cars and had no compelling desire to live forever. 
  Traffic was sparse when I pulled onto the expressway. Speed limit was 50, so I kicked the rented Toyota up to 55 for openers and was immediately passed by everything on the road, most of it doing around 70 with a few much slower and a few much faster.  
 I reverted to my usual rule and stepped it up until I reached median speed, passing just as many cars as passed me. 
  I haven’t seen figures, but I’d guess the accident rate is high under these conditions, not so much because of high speed as because of the wide range of speeds. That and the fact that, if all lanes are blocked momentarily making passing on the highway impossible, people sail by on the shoulder at high speed until they have passed the obstruction. 
  I’m not advocating we all go out and drive like hell as a way of speeding up traffic flow. Being a hopeless idealist, I’d prefer to see us regard driving as an important skill to be learned and practiced. Driver’s licenses should be earned through demonstration of skill and understanding, not handed out as an automatic rite of puberty.