In a Dutch oven or other heavy, lidded pot, heat the olive oil over medium-high heat and brown the pheasant pieces. Sprinkle some salt over them as they brown. Take your time and make sure everything is nicely browned, as it makes a difference in the final dish. Remove the pheasant and set aside.
Add the carrot, celery and onion and cook, stirring occasionally, until they are slightly browned, about 6-8 minutes. Add the garlic and cook another minute. While the veggies are cooking, mix the tomato paste in with the red wine and stir vigorously until they combine. Add to the pot and use a wooden spoon to scrape off any brown bits that have stuck to the bottom.
Put the pheasant pieces back into the pot, then add the thyme, oregano, rosemary, sage, cinnamon stick, vinegar, mustard -- and enough water to cover everything by about 1 inch. Bring this to a simmer and cook over low heat until the pheasant meat wants to fall off the bone. This could take anywhere from 45 minutes for a young, pen-raised pheasant to 2 hours for an old rooster.
Remove the pheasant and pull all the meat off the bones, and put it into a large bowl. Discard the cinnamon stick. Look at the pot, and if there is less than 2-3 inches of liquid in it, add some more water and bring it to a boil.
Break the spaghetti in half and toss it into the pot with the dates, pine nuts and raisins if you are using them. Boil the pasta in the sauce uncovered until it is al dente. Toward the end of cooking you may need to stir the pasta frequently because the sauce will be getting close to boiling away. If it does get too dry, add 1/4 cup of water just to loosen it.
When the pasta is done, turn off the heat and return the pheasant to the pot. Add the fresh herbs and toss to combine everything. Drizzle a little olive oil over it and serve at once with a light-bodied red wine or a hoppy beer.