Combine 1/3 cup of the olive oil, the lemon juice, garlic, 2 tablespoons of the marjoram and the rosemary, and marinate the lamb in this mixture for 24 hours. Bring the lamb to room temperature. Heat broiler and broiler pan. Remove the lamb from its marinade, scraping off as much of the herbs and garlic as possible. Season with salt and pepper to taste. Place it flat on the boiler pan, the thickest part at the back of the pan, and broil for 15 minutes. Turn the lamb and broil for 13 to 15 minutes longer. Remove from the broiler and let stand 10 minutes. Note: This is also an excellent cut for the grill; grill until a slight bit of pink remains in the center, either over _low_ direct heat, or smoke-roast over indirect heat. Let roast rest for 10 minutes before carving, and then slice off 8, 1/2 inch thick slices for the current meal, and then wrap, chill and refrigerate the remainder of the meat for use later in the week (see recipes for Deviled Lamb, Lamb Hash, Couscous-lamb Salad, Roasted Pepper, Lamb and Watercress Focaccia Sandwiches, and Lamb Pita Sandwiches with Tahini Sauce). Combine the potatoes, the remaining 2 tb. olive oil (or slightly more if desired) and salt and pepper to taste in a large roasting pan. Place the potatoes in the oven at the same time as the lamb goes under the broiler. Roast, tossing once, for 25 minutes. Add the zucchini and peppers, tossing them with the potatoes, and roast until the potatoes are tneder when pierced with a knife and the zucchini and peppers are just tender, 12 to 15 minutes more. Season with additional salt if necessary, pepper and the remaining 1 tb. marjoram. Reserve 10 potato wedges for hash later in the week. Mound the remining vegetables on a platter and serve with the sliced lamb and lemon wedges. Note: This recipe is for an oven with a single heating element that allows for simultaneous broiling and roasting. In an oven with seperate heating elements for oven and broiler, roast the vegetables first at 45 F., then broil the lamb. Reheat the vegetables in the 10 minutes that the lamb stands before carving.