Candy has a tendency to run over things in his way. Mostly he runs over Merlin or my feet. I have usually excused it as he doesn't know how wide his back wheels make him.
However, I recently noticed that when the baby gate is leaning partway into the doorway, narrowing the opening, Candy can judge PERFECTLY whether or not he will fit through, wheels and all. He is afraid of the gate crashing to the ground and will not try it if there isn't room to pass through. So he KNOWS how much room those wheels need, he just doesn't mind running over Merlin's legs or my feet, and he does mind knocking down the baby gate.
Maybe I need to crash the gate to the ground the next time he runs over feet.