The author is overly self-congratulatory I think. An article three years ago (Even though the byline date is more recent. A database update that didn't preserve timestamps? Or sneaky SEO to make it appear more relevant?) says much the same thing with more details about how the testing is done. <a href="http://www.racecar-engineering.com/articles/nascar/the-secrets-of-laurel-hill/" rel="nofollow">http://www.racecar-engineering.com/articles/nascar/the-secre...</a>
It's called a run down test. You accelerate to a certain speed, and then coast and the way the car slows down is where you get the data from.<p>It's not a new idea. Teams including Audi's Le Mans squad use it. Teams have rented the Shuttle landing facility at Cape Canaveral to do the same thing. The advantage of the Tunnel is there are less variables to contend with such as things like wind.