In large nonstick skillet, cook chops in 2 tbsp. oil over high for 5-8 minutes per side; season. Transfer to plates. In same skillet, cook butter, pears, sugar, and 2 tsp. vinegar, covered, over medium-low, stirring often, until tender, about 5 minutes; season. Transfer to bowl. Add remaining oil, remaining vinegar, and radicchio to skillet. Toss until wilted; season. Top chops with pears and thyme. Serve with radicchio.