When slow-moving, heavy trucks block the highway all traffic slows down. But does that mean that safety improves?

The above photo is a frame capture from one of the video cameras used in a study of traffic conditions on Highway 401 by Gorski Consulting. When heavy truck speeds are limited to a maximum of 105 km/h this can cause all traffic to slow down because those trucks block the passage of faster moving vehicles. That was likely a decision made by Ontario’s Ministry of Transportation to reduce speeds without using police to enforce speed limits. Is this method of speed control a good idea? What happens when slow-moving trucks interact with fast-moving cars? Do conflicts develop? This are some of the questions that may be answered in the detailed study that is presently on-going. Some results from the study will be revealed soon as they become available.