Preheat grill to 350° to 400° (medium-high) heat. Remove leaves from 1 rosemary sprig. Chop leaves to equal 1 tsp.
Bring balsamic vinegar, 1 Tbsp. honey, and remaining rosemary sprig to a boil in a 2-qt. saucepan over medium-high heat. Cook, stirring occasionally, 14 to 16 minutes or until thick and syrupy (about 1/3 cup).
Meanwhile, combine mustard, next 3 ingredients, chopped rosemary, and remaining 2 Tbsp. honey in a large zip-top plastic freezer bag, squeezing bag to combine ingredients. Add pork, and seal bag, turning to coat. Remove chops from mustard mixture, discarding mixture.
Grill pork, covered with grill lid, 4 to 5 minutes on each side or until a meat thermometer inserted into thickest portion registers 150° to 155°. Let stand 5 minutes. Transfer to a serving platter.
Remove and discard rosemary sprig from balsamic syrup. Serve syrup with pork.