Reviving I-401 entirely by accident? Not-very-well-executed retreat and evade? Inadvertently dropping the "I am your God!" on to a whole -host- of unexpected Fog ships?

You were right, Gryph; Corwin was well and truly off his game. For good reason, and entirely understandably; but certainly off his game; at least for the first half.

But this was still -phenomenally- enjoyable. I got as far as this:
>>There were six of them that he could see: the carrier, the battleship, and
>>four much smaller vessels, each all but identical to the other three.

and realized -precisely- who those "four smaller vessels" must be. I didn't stop grinning from there.

I think what I like most about this piece, is how expertly the KanColle and Arpeggio aspects dove-tail together. The Fleet Girls used meshed perfectly with the idea of Fog ships figuring out this whole "Mental Model" thing, and having seen both series I was able to very clearly hear each one. Kudos on that once again!

Seeing the ripple effects of this as it continues to play out are going to be spectacular.

-Droken