1. Preheat oven to 350°F. Coat deep baking dish with cooking spray.
2. Whisk together 2 Tbs. maple syrup and vinegar in bowl. Place blackberries in large bowl, and drizzle maple mixture over them. Add sugar, 3 Tbs. flour, and 1/8 tsp. salt to berries; toss to combine. Transfer to prepared baking dish.
3. Combine remaining 13 Tbs. flour, oats, pecans, brown sugar, and remaining 1/4 tsp. salt in separate bowl. Drizzle oil and remaining 3 Tbs. maple syrup over dry ingredients. Use fingers to combine thoroughly until small clumps form. Arrange topping clumps over berries.
4. Bake 30 to 45 minutes, or until topping is lightly browned and berry juices are bubbling just around edges of crisp.