That is a solution.
1) We should not do construction on every major highway every summer. Come April every year, there is construction everywhere. Therefore, the zone is 45 on every highway. When people see this, they say screw it and speed since they know they can't escape construction anywhere. Due to this, some of my best riding happened last November when they stopped carving up all of the unbroken roads
A construction is not everywhere
B Most are artificially in a hurry, and no real need to say "screw it" and speed
2) As was suggested, don't block off fifteen miles for 50 yards of work, people enter the zone ten miles ahead and speed up since they haven't seen a worker or cop for miles. Smaller zones would increase the effectiveness of the signs.
This is one of the problems, change in lane configuration. Most drive the same route every day. If you change configuration more frequently, then you allow more room for those drivers to make an error and crash. If you change the lanes once to allow for construction, and then reopen the new areas, there is less chance for the brain dead public to crash.
3) Screw all of the fines, tell the folks if you hit a worker you won't see daylight for a very long time. The first person to smash a worker gets put in jail for a while, blast the case on every media outlet; people will get the message and won't hit workers.
OK ...if I read right, you want to kill a worker to prevent worker deaths? Is that a part of your hiring package?
Plus, we don't have the testicular virility in this country to dole out the types of punishments necessary to curb crime and injustice. We are not talking about worker safety, for the most part we are talking about people balling up their cars on the highway, which at high speeds, can be fatal.