and I have to state "I have a CPL-ASEL with Instrument Rating, Helicopter rating with PPL privileges, tailwheel endorsement, Light Sport privileges for Gyrocopter". Are you sure I don't have to give the certificate number as well? And this being EASA-land, also the list of types on which I am type rated?.
If you understood the Manual and the procedures you would have read that additional information may be passed if relevant, there is no International requirement to include such information. It might also help to include your present position if you want anyone to find you!
Roger dates back to a time when messages were passed using Morse and may have been in code so the operator would have no idea of the content, but could acknowledge receipt!