It's not mixed in to be clear. The small pieces are still significant in size and filtered out. You can have more surface area of oak and impart flavors faster.

It's not mixed in to be clear. The small pieces are still significant in size and filtered out. You can have more surface area of oak and impart flavors faster. It's a way to effectively age wine faster with less resources since stainless steel barrels with finger sized chunks of oak have more oak to win contact. This probably ties in with the topic above. If your wine ends up with the exact same composition as more expensive wines but is made with fewer resources and the only way you can differentiate it is with knowledge of the label then perhaps the wine industry has missed the point.