The problem with this response is that the the "code itself" is not the authoritative documentation of what should be done. The "code itself" is what was done a

The problem with this response is that the the "code itself" is not the authoritative documentation of what should be done. The "code itself" is what was done and could be absolutely, completely wrong. The point of separating documentation and code is that the assumption is that the documentation (design) is correct, having been reviewed and the code should implement it correctly, correctness being verified by review and testing. Those strict processes should absolutely operate on code, but they are useless if they operate only on the code.