Charley,
Copy is in CAP 413, albeit not in the context to which you refer. One thing to bare in mind, is that you may not have heard the whole conversation. I have definately noticed a much quieter or even silent radio when the the fin is blanking the line of sight to the ground station.
Scuawasp,
I agree. I found the RT practical useful. Especially so as it exposed a complete misunderstanding of FIS that may not have come to light until after my skills test!