Hi Hoogl
thank you for the warm welcome. All previous cooks have gone great, with or without the guru.
I did wrap it tight but i'm sure there is room for improvement, next time i'll foil and broth it I think as it was my fist time with butcher paper. But regardless a 23hr cook, a chunk of it at 270f should have gotten the temp above 172. I'm baffled by the whole thing.
Ordered a whole brisket for the coming weekend to have another go so i'll update here.
Weirdest experience.