My technique is to "shock" the meat (not sure of the right term here) and then turn the heat way down and go low and slow... So for example.... If I have a 5 lb shoulder roast I'll go 1/2 hour uncovered at 475F and then turn it down to 200-250 and go another 4 or so hours (still uncovered) or til it's about 165 internal on a meat thermometer. The 1/2 hour at 475 forms the crust and seals in the juices.