but hover each one just above the water for about 5 seconds before gently putting it in. This prevents the shells from cracking due to shock of the hot water

If you want to keep your eggs from cracking from the temperature shock, put them in a bowl, fill the bowl with the hottest water you can get from the tap and let it sit for a minute before you put the eggs in the boiling water. Unless you have some crazy volcano of a hot water heater, the tap doesn’t get hot enough to crack the shell, but will warm the shell up uniformly to much warmer than you’d get hovering the egg, or doing that weird thing where you try to lower the egg into the water a teeny tiny bit at a time.