I think this article is more about the role of regulation in producing sustainability. I’ve long maintained that sustainability must also be an economic benefit or it won’t happen. and that holds true for truck fuel consumption and emissions. The dollars at the pump won’t do it. Truck owners are just like car owners– they often tend to drive an older model for years rather than buy a new one. Remember ‘cash for clunkers’? An incentive is needed to get them off the road. And engine and truck manufacturers are not eager to change models too often because of the setup cost to change the model. So maybe the EPA is doing a good thing to get folks moving.