Very few pilots have read CAP413. Why? Because there are hundreds of pages of Zzzzzzzzz......
And those of us who work with protocol definitions every day can be immensely frustrated that this document seeks to be the definition of a protocol ... but never actually defines it!
If you try to
teach something by example that's fair enough, provided you can pull the real definition off the shelf to resolve any issues, but you can't
define a protocol by example.