Strip the stems from the greens (unless they are very tender) and wash thoroughly. Place the greens in a saucepan and add the pork, water, and salt. Cook, covered, for 45 minutes over medium heat or until tender. Remove the pork and pour the greens into a colander to drain. Place the greens in a pan and chop, scissor-like with 2 knives. If necessary, add more salt, to taste. Keep hot and add the bacon drippings and a pinch of sugar.