The answer was pretty simple once you've done it and the experienced cooks above answered it with even the extra tidbits.
The larger mass may allow door opening without losing much heat and also keep the therm more stable and like cal says,seems to cook better overall.
As does the stickburner Max mentioned.
Although we talk about leaving the door closed on these cookers,a full load will buildup a lot of humidity and occasionally we might open the door to dump some moisture from the cooker which could also be a time to flip/rotate meats-or even spray them,if you are so inclined.
Some folks,as they gain experience and take notes about their tastes for smoke,might even add another small chunk of wood.
Just cook them simply and enjoy.The cooker will take good care of you.