Highway 401 Widening - Highway 8 to Townline Road

[Canard]

There is one other big factor I haven't seen brought up with all of these different concepts, and that is that people will generally follow at a time-based headway, not a distance-based one. In other words, at 100 km/h, people are supposed to leave a ~2 second headway, but realistically that is probably closer to 1 second in heavy traffic. If more cars come onto the highway, people cannot maintain a 1 second headway... Without slowing down. Slowing down permits the headway to remain constant: essentially this is the lane capacity (how many cars per hour per lane). If there are twice as many cars on the road, but the lane capacity is constant, speed must halve.

So, that's why I'm getting at the zipper-vs-queue thing not being as big a factor as all these articles and video clips make out. It doesn't matter, because at the end of the day, if you do the zipper and make full use of the right lane, all you've done is added a storage area for a few dozen extra cars, that's it.