I take he does not discuss whether he actually ever did that.
I have personally purchased Toyotas, Hondas, and a Volkswagen this way. Some of my students at NYU have taken up this method and bought cars this way too... They and I have always beat the price quoted on the Internet with this method.
He further claims to have once saved $1,200 over the price quoted on the Internet for a car he negotiated for his daughter, who was 3000 miles away at the time.
Apparently being a game theory expert does not prevent one from being a badass negotiator.
Why did you guess otherwise?
Here's the new thread for posting quotes, with the usual rules: