Not getting into the food chemistry but boiling eggs a shorter, high heat cook causes the negative reaction of the sulfur and iron in the eggs. This produces the dark ring outside the yolk and the strong sulfur smell. I found a much harder time peeling the eggs when this happens.
Place eggs in pot, add water one inch above eggs and bring to a rapid boil. Once boiling, remove from heat and cover for 17 minutes. Drain hot water and add very cold tap water. For me, this method has never produced that dark ring and strong egg smell and is easier to peel.
When eggs are cool enough to handle, cracks eggs thoroughly all the way around and place back in the cold water. Let eggs set in the cold water for at least 10 to 30 minutes. Water will get under the membrane between the white and the cracked shell and peel much easier.
I tried piercing the eggs before the cook and ice in the water to super chill the eggs after the cook and both steps were unnecessary IMO.
I absolutely hate kitchen gadgets as cluttered drawers and cabinets aggravate the hell out of me. I like the KISS method, however, I used one of these at a friend’s house for making a ton of deviled eggs and it was super fast. Poor quality gadget and I would never buy one but it was fast.
http://www.eggstractor.net/