Sorry, but I'm gonna have to disagree on this one, mk1. Although the writeup suffered a bit, if you look at the various case studies and their resulting data, the results were pretty clear. While there was a precipitous drop in air temperature, the meat temperature was hardly affected at all, as long as you didn't keep the lid open for extended periods or open too frequently (the exaggerated case). The thermal mass of the meat was insensitive to short drops in ambient temperature, i.e., the cooking didn't stop. Especially in cases where there was an adequate supply of fuel to facilitate a prompt recovery in air temperature. The point of the article was meant to say you didn't have to keep the lid closed the entire time and not open it until the meat was done - it's OK to look.