A little more data for you. What kind of advantage do you get by starting with beer that's already been refrigerated? Data below is based off the same basic setup as the last installment. Ice Mule Pro Cooler, 10 pounds of ice, salt. We probed 2 Michelob Ultras: one from the refrigerator, and one that was room temp.
The pre-chilled beer is getting in the slush zone by 15 minutes.