I often wonder at what goes on behind the scenes with political/regulatory legislation. The UK has professional lobbyists pushing a particular case and I wouldn't be surprised that over the years emissions regulations have come about as compromises built on influence of such groups. The mismatch of reported mpg of cars based on the "standardised" lab tests versus real life mpg seems to be a symptom of such compromises. I remember car mpg being pushed as a major selling point until questions about the achievability began to be asked. There has been back tracking to stress in small print that they are for comparison only. Marketing clearly diluting the negativity of the early "misquoting". I wonder if the car makers had influence on the test but suddenly had loopholes closed. If the test criteria could be constructed to leave room for "cheat options" then car makers had options to get benefitial results leading to better sales. Perhaps even keep improvements secret in the background until they needed them to gain an edge. The bottom line is profit. Decisions will be made appropriately. Influence will be wielded to suit.
