I'm saying it's best to smoke a brisket as a whole packer because of the fat content, (fat=flavor).You're saying it's best when you cook a packer without separating it, or by buying a packer you are guaranteed the two pieces belong to each other?
The flat is a very lean piece and the point is very fatty.
When smoked together it makes the brisket more flavorful and more moist than smoking as a separate piece..
I have learned my own method of doing briskets and it works well for me.
I don't go by temps, as some suggest.But I must say most of the time the temp range of 190º for sliced
and 205º for pulled is darn close. And is a good base temp for brisket.
I have learned that all meat is different and I'm sure most of my fellow members will agree.
(It's done when it's done)
This is the way I do it,
When the point gets "tooth pick" tender I pull the packer and separate the point and the flat.
Foil the flat and continue till it's "tooth pick" tender.
Foil the point and let rest till your flat is ready to pull.
Then you can cube your point and make your burnt ends.
Slice your flat and your ready to serve.
There are many variables that will effect the outcome, such as pit temp, spikes in temp etc...
But if you trim any fat (Al will agree),place it on the rack above your brisket, you will be blessed
That's my 2¢, hope it helps