Great enhancement, love it.
Correllation works well for me, maybe a little bit too aggressive. With ca 10 different clusters i have seen now, there was one instance where the stories were related, but different enough in level of detail that I wouldn’t have clustered manually. But definitely good enough to be useful / launch-ready and an great overall improvement to not have clustering.
Marking all stories in the cluster as read/unread doesn’t work for me, although I have premium archive.