I was just out grafting my persimmons today and took note of the condition of the varieties. My Chinubli graft came through OK, though there was tip dieback. Vaniglia didn't make it through my -10, even though it survived -11 for Cliff. Huk Gam and Miss Kim also made it.
I grafted Nikita's Gift and Kasandra today (thanks SMC!). Hope you saved a bit of Kasandra to re-graft. Cliff says that it has survived -16F without damage, so as you said, it must be the swings.
I'm surprised that Tam Kam made it for you with a -12F low. Did you protect it? Mine survived the first few winters -3F and -4F, but the last two (-9F and -10F) have killed it back to the wood-chips I insulate it's base in. I think this is the last year I let it re-grow. If it dies back again, I'll graft something hardier at the base and maybe keep just a branch of Tam Kam.