What NOT to do with a hung up tree

On my chainsaw training I learnt that there are several things you don't do with a hung up tree:

• walk under it
• climb up it
• cut bits off the bottom of it
• fell the tree it's leaning on
• leave it unattended

You can see how we dealt with a hung up tree in another post here, using a winch and a pole.

So you can imagine my horror watching this video I came across on YouTube, which I must stress, did NOT happen in our wood, and I don't know the people involved, who thankfully didn't get hurt:

The original video is here: http://www.youtube.com/watch?v=HZ2lIUW5bKw

Mike