There are plenty of stories doing the rounds of the RAF doing exactly the same trick with Land Rovers.
Lets face it, airdropping vehicles is never going to be a 100% guaranteed delivery.
But the top brass need to know what percentage will work, so they need to find out.
In the greater plan, the cost of a few Humvee's or Land Rovers ain't a lot. Less that the fuel bill for the flying thinggies.