MD: (10.8) "After retiring a channel, the client..." makes it sound like the client sends MC_RETIRE. How about "After receiving MC_RETIRE,..."
To add to your explanation about RETIRE_CONNECTION_ID, this frame is sent by the creator of the connection ID, which receives packets with that CID. The valence here is different: the creator of the channel ID is also the sender.
MD: (10.8) "After retiring a channel, the client..." makes it sound like the client sends MC_RETIRE. How about "After receiving MC_RETIRE,..."
To add to your explanation about RETIRE_CONNECTION_ID, this frame is sent by the creator of the connection ID, which receives packets with that CID. The valence here is different: the creator of the channel ID is also the sender.