"Discard" is a term used by some bakers for excess sourdough. I think it's a terrible name as it reminds me of waste, something no one in the world of food much wants to encourage. Recently I found out that a niece of mine in Switzerland had quit her bakery apprenticeship at what was supposedly a first class establishment. I asked why she had quit.  It seems waste was rampant, discarding trimmings. Discard wasn't recycled or used. She was disgusted and couldn't see herself in that vicious circle. Thinking about her commitment and passion, I experimented with croissant scraps – incorporating them into a milk dough. Viennoiseries, for instance, can be layered into non-laminated dough, introducing a different feel (feuilletages) of flakiness. No waste, just pastry… kaboom!