Distribute the arugula evenly among four serving plates.
Put the pancetta into a medium skillet over medium-high heat and cook until really crispy, 3 to 4 minutes. Remove and drain on paper towels.
Put 2 tablespoons butter and the oil into the skillet and reduce the heat to low. When the butter has melted, place the pears in the pan and season with salt and pepper and 2 tablespoons honey. Turn up the heat to medium and cook until the pears are lightly caramelized, about 5 minutes. Add 1 tablespoon vinegar and cook for another minute. Remove the pears from the pan, reserving any juices that may be left.
Arrange the pears and pancetta on top of the arugula so each serving has 4 pear quarters and 4 slices pancetta.
Put the pan back on medium heat and add the remaining 1 tablespoon butter, remaining 1 tablespoon honey, remaining 2 tablespoons vinegar, mustard, pine nuts, salt and pepper. Cook briefly until the dressing is heated through. Pour the dressing over the salads, then scatter over the gorgonzola crumbles. Serve immediately.