When I watched it I wondered if the winch line should have been in line with the track going down the hill? With it at that angle as soon as it started to slide it was pulling the truck over the way that it was already leaning, so it didn't take much to push it past the point of no return.
It's a live and learn thing. It was only a hobby truck for him and I don't think he'd had it long. He's sold it now and moved on to other toys. Shame really as he's a top bloke and helped me a fair bit talking about the mechanical side of things. I'd have liked to go off roading with him at some point when I get my own truck.