Rinse capon pieces and pat fry with paper towels. Put pieces in a large bowl and season generously with salt and pepper. Combine the rosemary, the sage, minced garlic and olive oil in a small bowl and add to capon. Sprinkle with paprika, and mix thoroughly to coat capon pieces. Let marinade for 1 hour.
Preheat oven to 450ºF.
Add potatoes and whole garlic to capon and toss to coat. Pour the capon, vegetables, and marinade in a large roasting pan, and spread evenly in pan. Roast for 25 minutes, reduce oven temperature to 400ºF and continue roasting for 45 minutes to one hour or until capon pieces are tender and the potatoes are golden brown. Baste occasionally with pan juices.
Place the capon and the vegetables on a serving platter. Discard most of the fat from the pan and add the vinegar, scraping the bottom of the pan and mixing together. Spoon the sauce over the capon and the vegetables before serving.