What I have learned is that it can't stay uncovered on a kamado for the full cook time. If you try that, the flat gets dried out. Once it reaches 170ish, you have to cover it. It doesn't matter if it's foil or it's butcher paper, but it's necessary. I also turn it over to the other side once I cover it. I just find that even though the temp is at 250, the bottom just gets too hot and dries the undersurface of the brisket.

I often let my briskets sit in a cooler with "meat towels" for 4 hours or even longer. I don't know if this makes a difference, but it certainly doesn't hurt anything.

Salt and pepper is king and nothing more is needed when it comes to brisket.

My kids will tell you that the single best thing I make are burnt ends from the point of the brisket. In doing this, it seems like it dries out the flat (because I have to take it out of wrapping, separate, and re-cover). But they don't care because they love the burnt ends so much.

There is nothing wrong with a slightly dry flat (if it comes out that way). Just slice it a bit thinner and use the left overs for chopped beef sandwiches, pit beans, nachos, and salad toppings. It's good with everything.