To cap off last night's tale, today while I was fixing Z.'s lunch, I stepped out of the kitchen for two minutes. In that timespan, he leaped on to the counter, stole a piece of cheddar cheese, and leaped down and was eating it on the ground. Mind you, I have never known him to eat cheese before this point.
I am beginning to worry about leaving him here to his own devices when we go away for a few days for Christmas. He might actually wreck up the joint.