Hello all! I have read many things on wrapping your end product in foil and putting it in a cooler with towels. I did so last weekend, letting my sirloin tip rest wrapped in foil for 30 min in a soft sided cooler, with a warm pack and towels stuffed full. But my temp did not rise at all. In fact, it lowered by 10 degrees. Should I not be using a soft sided cooler? Do I have to do more layers of foil? Any thoughts you might have would be very helpful. Though the meat was still a fine temp for eating. I was just curious about the many, many reports of temps climbing for awhile during resting. Thanks!