EV -- I'm happy you liked your brisket with this "killer" recipe. If you & the family or whomever you're serving are happy, the smoke was a success!
That being said, I'm with Smokin in that I'm a traditionalist when it comes to brisket. Personally, if I were gonna put out the $$$ for "Waygu," the smoke would go au natural - my traditional smoke.
This recipe has to be good. A bunch of people have raved about it! Just giving my $0.02 worth.
Keep on smokin!