I bought a fresh 5 kg goose from Waitrose (about 11 lb). I pricked the skin, rubbed oil over it and rubbed in sea-salt. It took about 3 hours to cook in a 170 fan oven, lightly covered in foil, and basted occasionally. No stuffing. I par-boiled the potatoes for 8 minutes, then roasted them in goose fat at the bottom of the oven, having first roughed up their surfaces by shaking them in a pan.
I served it with sautéed peppers and mushrooms and Yorkshire puddings. Gravy for the puddings, Bramley apple sauce for the goose. The wine was a New Zealand sauvignon blanc, and the dessert was a Remy Martin 12-month aged Christmas pudding with brandy butter. Mmm.