I know that when Stone/Victory/DFH made their Saison Du Buff, they added the herbs in the boil. Not sure for how long though.
Caspean Ales and Cider
“There is an ancient Celtic axiom that says, ‘Good People Drink Good Beer.’ Which is true, then as it is now. Just look around you in a public barroom and you will quickly see: Bad People Drink Bad Beer. Think about it.”
-- Hunter S. Thompson,