Charging for waste/culling on board-by-board selects

I am curious how you all handle waste factors on higher-end builds like Massaranduba where the mill run seems to be getting choppier. I usually quote a flat 15% overage, but on a 600-square-foot deck project last month, I ended up pulling 10% out of the pile just due to heavy end-splitting or bad milling that didn't pass the quality check. That cuts deep into the profit margin when the client expects perfection on every exposed face. Are you guys building a separate line item into your estimates specifically for 'material culling and site sorting' to account for these factory defects, or are you just eating it and passing the cost into your hourly rate? I'm tired of playing the game of trying to flip boards around to hide defects just to keep the waste percentage in check.