There's a lot of variables such as rub, type of smoker, cook time, temp, etc... I always get a decent bark even when foiling So its hard to say if higher to lower would give a thicker bark. But I would think a lower temp over a longer period would give a deeper bark (thicker) As far as bark goes and many folks may not agree... I think the best bark is if the butt is foiled. This makes an otherwise hard bark chewy... which is what I like. I'm always amazed at how many folks say you don't get a good bark when foiling. Its actually a great way to controlled the bark formation as well as the texture desired. That's reffering to my pit of course. did I answer the question? lol.