1. In a 9 X 13 inch baking dish, mix wine, say sauce, oil, garlic, chopped cilantro, and bay leaves. Spread lamb open in the marinade and turn to coat. Cover and chill, turning meat occesionally, at least 4 hours or up to 1 day.
2. Lift lamb from marinade and lay flat on the barbecue grill over medium heat. Close lid on the grill. Cook, turning as needed to brown meat evenly, until a thermometer inserted in thickest part is 135* to 140* for rare, 30 to 45 minutes; thin portions will be well-done. Brush meat occasionally with marinade up untill the last 10 minutes of cooking.
3. Transfer meat to a platter, keep warm, and let rest 5 to 15 minutes. Garnish with cilantro sprigs. Thinly slice meat. Add salt and pepper to taste.