If you want to fly from Toronto to Manchester, New Hampshire on June 24th, Air Canada’s booking engine offers you two options:

You can fly direct, which takes just under two hours and involves a tiny Beechcraft airplane, or you can fly via Winnipeg and Chicago, which takes 10 hours and involves traveling an additional 3,340 km. Wouldn’t it be a good idea to have some sort of “filter out insane flights” tool on AirCanada.com?
Comments
At least the fares for that flight discourage the insane flight. I was trying to book a flight from Calgary to Dublin last year and the Calgary-LA-Dublin option was the cheapest. I selected the more expensive and but much more direct Calgary-Chicago-Dublin filight.