Extraordinary and thought-provoking. It seems to address some of those irritating snags left dangling after DH - the issues of house rivalry, and grudges continued not just through a lifetime but through generations, that the epilogue dealt with simply by Harry's comment about Snape as a Slytherin, and the bravest man etc.

I read it some hours ago, & it's still drifting through the back of my mind - all the "what ifs" and the regrets, the remorse, the guilt. It has some similarities with some of the other of your fics that address survivor's guilt, but what is really intriguing here is the way that the two central protagonists are such callow, incomplete characters at the opening of the fic, and finally develop understanding & humanity during the story's unfolding - their evolution of the spirit.

Masterful work, wonderfully written.