Ofcourse not
Resources free by reduction in memory copying negate the overhead that required thread synchronization adds.
For uploads, I expect tremendenous performance improvent; seperate encryption thread pool is now gone - io threads are able to transform themselves to encryption threads when required. This means that thread is in many sitautations able to decrypt/encrypt/chash/whatever the buffer immeaditely after processing it. Just like with the old core, amount of threads performing such operations simultanously is definable parameter.