Lol @ the headstand.
Really though, this is no worse than training a dog, though I've never used shock collars or whatever.
The chains were longer than the ropes. The ropes are the true constraints, which don't cut them up like the claimed the chains do. You teach them that they can't break the rope, and when they are adults, they won't even fight against a thread of floss. That's not really that cruel. It just keeps them from destroying everything by freaking out.
Of course, I'm speaking from within the parameters of "a life of an entertainment elephant." That sucks and is cruel in general. Nothing should be caged. If it wasn't yanked out of it's normal environment, it would get to wander around and trample all of the gardens in Africa until GoDaddy's founder went and shot it with a bazooka and then posted the pictures on Instagram.