Too many drivers take significant risks to save a few minutes on a long trip. People become frustrated at slow trucks on hills and often the speed limit gap between the normal speed limit of 110 and heavy vehicles at 100.
The difference usually means cars may pass quite a few trucks, but they will also have plenty of safe opportunities to do so. They can accelerate quickly, as opposed to the slower acceleration of larger vehicles and often limited chances to pass slower traffic.
The practice of trucks flashing the right-hand indicator to help someone get around is now illegal. Some drivers may still not be aware of this, and it would seem many drivers still expect it. Judging by the number of people who appear to wait to be given a flash and having followed the truck for a while will decide almost on the crest or corner that they must get past this truck. Every truck driver has experienced the same thing many times, and the resulting near misses leave one shaking your head in disbelief.
A semi-trailer is 19 metres long, and a vehicle showing a “Long Vehicle” sign (mostly B-Doubles) will be 25 to 26 metres long, so you are attempting to pass 9-10 cars at once. Perhaps if that thought prompts one to have sufficient vision of clear road before trying to pass it will be worth remembering.