I've only cooked 5 or 6 butts,but the best ones have been the last couple that I've foiled.
I cooked at 240-260 until the internal temp reached about 160 and then wrapped in double layers of heavy duty foil until the internal temp reached 185-190. I then unwrapped and cooked until I got the level of doneness I wanted, usually around 200 degrees. I spritzed a couple of times after removing the foil.
I get better results by foiling ribs and butts.