I recently signed up for America's Test Kitchen Cooking School and followed their directions for poaching eggs. I brought my water w/ vinegar & salt to a light simmer, removed it from the heat, and gently added the raw eggs at the same time. I covered and left it for 5 minutes, saw they were a bit feathery, gave them an extra minute before removing them, and found that they were still feathery and a bit undercooked.
My guess is that they need more time or persistent heat since I'm at higher altitude (mile high in Colorado), but I'm not sure. Should I keep the heat under the pan? Should I keep the eggs in longer? Maybe both?