A whole-code dimension constraint

If $C$ is the entire unknown $n$-qubit input and only $k$ qubits are accessible, this gives ${\epsilon }_{\mathrm{rec}}\ge 1-2^{k-n}$. A claim of accurate whole-code recovery after half the qubits must therefore change its input target, output dimension, or access assumptions. A small diary inserted into a previously correlated system is not this whole-code task HaydenPreskill.