My list of things for preventing tough, dry meat (in general, but applicable to q-ing)
1. Bring meat up to room temp before cooking
2. Sear meat before cooking: Use a veryvery hot oven (500 degrees or so) OR Fry on all the sides on the stovetop in hot grease OR immerse in a fat fryer (I will be trying this for a brisket in the future)
3. Do not Salt before or during cooking
4. Keep temps below 210, even lower when possible/practical, but at least 160.
5. Use a moist heat.
6. Avoid forks or other piercing instruments while cooking or resting, as the juices will leak.
7. Wrap the meat tightly after cooking in film or foil and bring them temp down slowly
8. "Lard" the lean cuts (that is lay some fat, like bacon, over the lean parts) when cooking.
9. Let the meat "rest" at room temp for at least half an hour before slicing
10. slice at an angle, rather than straight up and down. Instead of 90 degrees, hold the blade at about 75-80 degrees. This will help cut through more of the grain.