Speaking of cold water to stop cooking. I have a method for great hard boiled eggs - for eating right now or deviled or whatever.
1. Cold water to cover the eggs.
2. High heat to bring water to a rolling boil. Set timer for seven minutes when they start to boil.
3. Reduce heat slightly but keep a decent boil going.
4. Get a bowl of ice water ready. When seven minutes is up, put the eggs in the ice water. Let them set a few minutes.
5. Start peeling at the fat end of the egg. They peel great, they are more tender than most any HB egg I've had and the yolk is done and also tender.
Give it a try. No joke.