As for [[.bmmtools_recovery]: dplyr::select() on a tibble subclass
subsets through [ and never reaches dplyr_reconstruct(), so this
method is what drops the class once a contract column is gone.
As for [[.bmmtools_recovery]: dplyr::select() on a tibble subclass
subsets through [ and never reaches dplyr_reconstruct(), so this
method is what drops the class once a contract column is gone.