I'd say your mental picture is pretty accurate lol. Don't forget, he got a full walnut out of this experience too. Banner day in his world. Mine as well, but not in a good way.
Dorian's groomer has a cockatoo that did a similar thing. She now tapes the boxes to the kitchen counter so she can't work her way over the edge. Thankfully, she wasn't hurt either. Gave her mom a scare though.