Harry is only smart when he has a chance to sit down and reason things out. The Peace Talks gave him no opportunity to think. First, he was too busy rescuing Thomas, then watching Mab get bitch slapped, then fighting Eb, then securing Thomas. Things rolled right into Battle Ground. Which was a non-stop slugfest.
Thematically speaking, expect Thomas to be off the board for a couple of books, at least. Harry is being stripped of his gang to make his last stand solo. Chances are there will be more deaths, enforced separation and possibly someone (Molly?) will apparently align against him. But the Scooby Gang will be reunited for the BAT, mark my words on it.