That's strange cause that link worked at home and here at work for me. It's just a link to a small quicktime video though. If you don't have quicktime that would for sure make it so it doesn't work I suppose.
Basically, in a lot of the rally races and Dakar, you can't have support vehicles on the course during the race. So back in the day, people started entering actual dedicated support rigs in the race to follow along and help the primary race vehicle as needed. Fast forward decades and those support vehicles have morphed into those things and have developed a race of their own literally. I don't totally understand how the race vs. support duty goes for those rigs as it's a form of offroad racing that's still pretty foreign to me but that's kind of how I understand it. It even goes beyond those... The teams enter multiple cars in the race to use as spare parts... They'll start off with a primary racer, that's the one they're banking on and everyone's role is to support them. They break, the other twin cars catch up and they strip parts and keep them racing. Sometimes depending on circumstances those support cars end up the primary team car and actually switch roles mid race if say the primary car gets balled up or they just find that the primary car can't hold the pace of a support car/driver. Races like the Dakar where it's 5000 miles over like weeks turns into somewhat of a team sport with your support being every bit as important as the actual racer.
Those guys are arguably masters at securing cargo!!! I mean you think we strap stuff down... Think about what those guys are doing/using to secure a full spare parts supply for a race program in the back of a vehicle that itself is also racing! LOL
If you've never seen video of them, search something like "dakar big trucks"... They're mind blowing!