[magduf]

Yes, that's somewhat correct. I think it's more correct, however, to say that trucks (commercial ones) account for the vast majority of wear and tear. I've read that the wear and tear scales with exponentially with the weight of the vehicle, and trucks can weigh up to 80,000 pounds, far more than your typical car that weighs 3000 or so.

Of course, on residential roads, they don't usually have many large trucks. Also, in areas with snow, it seems that snowplows actually cause most of the potholes.