As a KCBS Certified Judge, I can say without question that I will judge each meat category to the KCBS standard. You have to judge whatever the competitor submits, and to the KCBS standard. In my limited experience, I have seen primarily chicken thighs (with an occasional leg and breast), pork butts, spares, and the hardest thing to cook, and judge, IMO, the brisket.
Brisket is supposed to be the toughest meat to cook, and it is (literally and figuratively). Chicken is next. It is difficult to not overcook, too much. Based on my limited experience ( and inputs from a number of seasoned veterans) the chicken skin is one of the first things to make or beak an entry. To get "bite-through skin" and not overcook the chicken thigh is difficult. Having said that, I have had more good chicken than brisket. I had several pieces of chicken thigh at my last judging that were really good. On the other hand, I had a piece of brisket that didn't look too bad, but I could have used it as a tow strap on a truck! It wasa way undercooked!
Basically, as a Certified KCBS BBQ Judge, you must put your preferences aside and judge to their standard. This is difficult, at first. After my wife and I took the KCBS class, we have become much pickier eaters of BBQ when we go out. She even "critiques" my BBQ cooking with these standards. Some days I win, and others we won't alk about!
Keep an open mind and enjoy the class. You will meet some wonderful people out there judging BBQ.
Art
I consider Hub to be a good friend. Extremely knowledgable about cooking BBQ, and willing to share his expertise.