I was reading an article about vehicle emissions and it made me think about all the manufacturers putting "Eco" modes into the engine software now. How do these different modes factor into emissions and fuel economy standards? As engines get more and more complex and variable what's to stop a manufacturer from having an eco mode that gets you 30mpg and 200hp available and then a "fuck it" mode that gets you 15mpg and 400hp (exaggerated and not based on science, but you get the idea)?

Have a picture of something that gets 10mpg on a good day for your time