Prepare a grill for direct medium-high heat (450°; you can hold your hand 5 in. above cooking grate only 4 to 5 seconds). Trim any hard fat from the outside of each lamb chop and season on both sides with salt and pepper. In a small bowl, mix 2 tbsp. oil, the lemon zest, and garlic; slather mixture on both sides of chops.
In another small bowl, stir together olives, parsley, preserved lemon, and remaining 4 tbsp. oil.
Grill chops 4 minutes, then flip and grill an additional 2 to 3 minutes for medium-rare. Transfer to a clean plate, tent with foil, and let rest 5 minutes. Serve each chop topped with a spoonful of olive parsley salad, and roasted or grilled potatoes if you like.
Note: Nutritional analysis is per serving.