Pulling any fixed object is dangerous. I had a neighbor nearly get killed pulling a tree with a NH TC33 via the FEL. He was backing up and had the loader up a few feet. The tractor was in 4x4 and about went over on him.
I am guessing what this guy was doing was pulling from a draw bar off the 3 point. Once it raises up past the axle center line its going over and usually ends up like this case. That's why tractors have fixed draw bars mounted below the rear axle center line.