It only gets interesting after about 4:30 - before that it's simply building a crane using an existing mobile crane (that just keeps getting longer and longer).
It's not really bootstrapping considering another crane is used to build the base of it...
Well, there's no reason it has to be that way, except money and time. One could, in theory, assemble the base and initial structure by carrying individual steel rods and buckets of concrete to the site and assembling them all.
But the astute (and, perhaps, perverse) observer would note that this only pushes the problem farther down the stack. Using humans to carry your parts to assemble the base isn't really bootstrapping, either, because where did the steel and concrete come from? For that matter, where did the humans come from?
Unfortunately, we don't yet know how to depict humans being bootstrapped from raw organic chemicals at this level of detail, and even if we did it would probably run a bit longer than 6:17.
There are two points that surprised me here:
1. Rods and pins are used instead of classic nuts and bolts;
2. Crane's extension.
It's amazing how self-sufficient a construction crane setup is.
I am surprised by the load bearing power of steel, the total height of a crane made of steel + the counter weight + the weight of what it's lifting, that's a lot of force at the bottom of the steel tower.
