"We fell in love with the way the beer tasted from the fermenter it was cellaring in before packaging, FV 7, and Tank 7 was born. Since then, we've modified the recipe just a tiny bit when we brew Saison-Brett. All the hopping remains the same, but we mash just a bit longer when we're brewing Saison-Brett. We really want the beer to dry out quite a bit before we add the brett. Since brett continues to chew away at sugars, we want to make sure we have a beer with a very low final gravity before we introduce the brett."This is an interesting quote. I think the old school of thought was always "you have to leave as much behind for Brett to chew on as possible". So it seemed like you would hear a lot of recommendations to mash high to leave a lot of dextrins as food for Brett.
This quote seems to line up with what I've been hearing more and more over the past couple of years - that Brett isn't producing it's typical flavor contributions through its metabolism of sugar and dextrins, but rather from converting other byproducts such as phenolics and esters produced by Saccharomyces in primary. If Saison Brett is produced like this, then that certainly cements it in my mind that Brett doesn't need dextrins to work as a secondary yeast.