Induced demand is one of those things that always struck me as an abused concept. Yes, it happens, but it's impossible for it to be always true. New roads will attract more traffic, but only up to a point. There exist roads in the United States that aren't experiencing traffic jams at rush hour. If Induced Demand were a law, that wouldn't be true. So you can't just say that building new roads won't alleviate traffic, period. There are cases where it is true, and there are cases were adding new roads actually make traffic worse, but there are also cases where adding roads (or tunnels) will alleviate traffic.