Let me fling my 2 cents in here. I am the cook for our competition BBQ Team the "PIT"sburgh Smokers. Up until recently I have been adding wood chunks as follows:
In my green egg, I put the wood chunks near the bottom of the charcoal so the wood burns early in the cook getting into the meat early on. In my other smoker that has a charcoal pan, I typically put the chunks near the back corner where the lit coals are put into firebox. Again, this gets the smoke into the meat early on.
I recently took a competition class with the Warren County Pork Choppers, look them up if you don't know who they are. I was taught something that floored me, and then Franco when I told him. They add NO wood when cooking brisket or pork butt. I know, I know, me too. That goes against everything I have always heard. I did a brisket this weekend with nothing but Royal Oak briquettes and got a dandy smoke ring. I used this same technique in our last competition in Harrisburg first weekend in October. Based on their technique, I only add 2 or 3 small chunks when cooking ribs or chicken. I'll try to post somepics of the turnin boxes later on.
One of the demons I have been battling is, my food always tasted great the day I cooked it, but the next day, or even a few days later, the smoke taste was almost overpowering, leaning towards bitter. Ever since I started this technique, that is gone, my food tastes as good 3 days later as it does right off the grill. With that being said, keep in mind that charcoal is made of what??? Wood right, so it makes sense that you would get a smoke ring from charcoal alone. It works try it. Try cooking a brisket on just charcoal and see what you get.
When I cook ribs or chicken on my egg, I only add 2 or 3 small to med chunks. I typically put a small layer of charcoal on the fire grate, put my electric lighter ring on the bottom layer, then a light layer on top of the igniter and fire it up. Once it gets going, I pull the igniter out, add a little more charcoal, then the chunks. then slowly add the rest of my charcoal. throw on the plate setter and crack a beer and wait for it to come up.
When I cook on my other smoker, I add a few chunks just shortly before I add the meat. Just enough time to let the chunks get burnin before I add the meat.
If you have some time try this, cook a small brisket on Saturday the way you normally would, then do another one on Sunday without adding and charcoal. Then taste it on Wednesday and see if you see the difference.
That's my opinion. Remember, "Opinions are like beer, a little is always a good thing, too much and you typically get beat up!"
Enjoy & Good Luck,