The CGSP kept a pretty consistent 250-270 degrees the entire time. When doing a whole bird I've nailed down the means to a tender, crispy skin. It has to be mopped every 20 minutes, starting approximately 45 minutes into the cook (or even earlier). And the mop has to contain some vinegar, and ideally a bit of fat - butter works, drip pan runoff works, bacon fat works. You lose a bit of heat so it takes a bit longer, but it's sooo worth it.