I usually cut an 8 lb butt into 2 pieces to reduce cook time, howsomever, last weekend I smoked two 8 lb butts just to see if I could (on the offset). I cooked one to 175 for slicing, the other to 200 for pushing.
Results were almost bad...too much smoke on the long cook. Since it took over 8 hours to cook, it stayed in the smoke way too long. It seems I forgot the king's method. Aaron smoked his for about 4 - 5 hours, then wrapped in foil JUST TO KEEP THE SMOKE OFF OF IT.
Henceforth I will follow that procedure when cooking for more than 5 hours. With a 4 lb butt, I may not need to foil at all.
Beware: this topic may be as volatile as "wood chips - soak or not"