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 cm 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, dozen 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 10ºC ., then broil the lamb. Reheat the vegetables in the 10 minutes that the lamb stands before carving.