Well it was very clear from the beginning that these were a set of debug commands. A back door would probably have a door knocking semantics and a very limited

Well it was very clear from the beginning that these were a set of debug commands. A back door would probably have a door knocking semantics and a very limited apparent surface. These were direct memory reading and writing command and were available in a standardized protocol. I would think the real issue was wether they were closed enough in real world design to avoid a security issue through debug means.