Remark: References are untouched unconditionally

For a state ${\rho }_{BT}$, the conditional $T$-state on outcome $r$ is the normalized $r$-block when that block has positive trace. It may depend on $r$. Equation (eq:drop-step) states that the unconditional $T$-marginal is unchanged. Conditional steering is not a failure of the complete identity. No normalized state is assigned to a zero-probability branch.