Watching that brings back memories; posted this a while back:
Worked a summer of weekends logging for a small sawmill in Heber Az when I was a lot younger. Got pretty good at dropping trees exactly where I planned. One tree in my cutting area was exactly halfway between two other trees that were about 16 ft apart, and it had an obvious wicked twist in the trunk. Being a relative newb, I asked the old timer who owned the mill how to approach the cut. His advice was about what I would have done anyway, so I proceeded. What neither of us knew or could see, was that the tree had grown with it's branches touching the other trees, with a huge preload from the twist. Just as it began to fall, the tree hopped about 15" off to the side off it's stump, rotated 90 degrees, and dropped about 20" to the ground, all in about 1 second. I was clear when I started the cut, but the rotation brought a branch directly above my head, and when it dropped, it rang my bell & drove me to my knees. Thank god for hardhats. The tree didn't fall, & it took two of us about an hour to drop it. Been pretty leery of twisted trees ever since.