I can't speak for how Franklin cooks his briskets, but I'm pretty sure he's using an offset smoker and not a WSM. I also can't argue with his success or wisdom. The man is the brisket king.
Most folks prefer to cook the point/flat combo. You'll need to separate them when the flat is done. The point is much fattier(internally) then the flat. Also you can make burnt ends with the point. If you decide on a full packer then you'll probably need to go overnight, if the flat - then I'd start it the morning of.
Good luck and keep on asking questions.
Chris
Correct on the offset, great book by the way.
So between my two localist meat markets, I can get a whole choice from one for $5.59 per pound (I think I have a coupon around for $5 off) or the other one has just flats for around $4.20 per pound...