A Real (Italian) Man’s Ragout (ragout =>ragù)

Ragù alla Bolognese

1. In a large, deep sauté pan, heat olive oil over high heat and add carrots, celery and onions. Cook, stirring, until vegetables are lightly browned, about 6 minutes. Add pancetta, and cook, stirring, 2 minutes. Add beef and cook another 2 minutes. Add pork and cook until meat is lightly browned, about 5 minutes.
2. Whisk together the tomato paste and I cup of the broth, and add it to meat. Place pan over low heat so that sauce just barely simmers. When broth has evaporated, add another cup. Continue to cook, stirring occasionally and adding a cup of broth when stew becomes dry, until all the broth has been added, about 3 hours.
3. Add milk and butter, and continue to simmer very gently until milk is evaporated and sauce is very thick, about 1¼ hours. Season to taste with salt and pepper, and serve over pasta, preferably tagliatelle or pappardelle.

If your heritage leans more toward southern Italy, you may view the above, northern derivative as heresy. Primarily due to availability of ingredients, a southern-style ragù is a tomato sauce with a hint of beef, whereas the northern-style is a meat sauce with a touch of tomato. At any rate, to avoid slighting anyone, the following is a southern-style ragù.
Note that the northern-style sauce traditionally is served with tagliatelle whereas southern-style is served typically over ziti or penne.
Can anyone explain those traditional choices to this Italian-disabled recipe hound?   As far as I can tell, pasta is pasta, i.e. the basic ingredients are similar so would not cause this difference.  Does the shape depend on how the sauce "clings?"

Ragù all Napoletana

½ cup pine nuts, coarsely chopped
½ cup raisins, coarsely chopped
4 cloves garlic, minced
2 pounds beef chuck, cut into slices 1/8-inch thick
Kosher salt and ground black pepper
5 tablespoons extra virgin olive oil
1 small onion, thinly sliced
¼ cup red wine
2 large (35 ounce) cans of high quality plum tomatoes
Cooked ziti or penne
Grated Parmesan for serving.

1. In a small bowl, combine pine nuts, raisins and garlic. Lay meat slices on a work surface, and season them lightly on both sides with salt and pepper. Sprinkle pine-nut and raisin mixture on one side of the slices. Roll slices up and secure them with a toothpick or tie them with kitchen string. Place them in a large, deep sauté pan and add oil, onion and 4 cups of water. Place over medium heat and simmer, uncovered, until water. has evaporated, about 1 ¼ hours.
2. Continue cooking, turning meat rolls with tongs, until meat is lightly browned on all sides. Add wine to pan and cook until evaporated. Drain tomatoes, reserving juice, and coarsely chop tomatoes. Add tomatoes and reserved juice to pan, and bring to a simmer. Cook until sauce is very thick, about 2 hours.
3. Remove meat from pan with tongs, remove toothpicks or cut string, and place meat on a serving platter. Season sauce with salt and pepper, and pour it over ziti or penne. Serve with meat and grated Parmesan cheese on the side.

Yield: 4 to 6 servings.

RAGÙ — The above recipes were adapted  from an article in the New York Times, Wednesday, May 19, 1999. Ragù all Napoletana was created by New Yorker, Sandro Manzo, who owns an art gallery in Rome and is an agent for Italian artists. Ragù alla Bolognese was created by Alex Goren, a financial consultant in New York City. Both emigrated from Italy, not surprisingly, Mr. Manzo from an area south of Naples and Mr. Goren, from the area near Bologna.