Remark: The concrete order-three interface

For the supported-sector reference in XIV-J, the intended local substitution is

in a specified response-normal chart in which $N_U$ is relatively closed. The copied reference and its collected coefficients are recorded in Section sec:reference CheungXIVJ.

The support hypothesis is essential. An arbitrary extension may also contain terms supported in $A$ outside $S$; such terms are not described by the response-normal insertions.