I can understand the burst delivered in a short interval of 220v, but the Heat Minder? Have you any noticeable occasions when this feature was critical to your cooking? I just don't understand why the turning off and on would be any different than a thermostat that regulates the temperature. Or is it designed to turn off the oven when temperatures are too hot, which occur more often at ? settings? Just trying to piece together the value of a Heat Minder.