I did an RT course once. Trouble was about 95% of it was irrelevant to gliding.
Permission to start up/taxi/take off? Not in a glider
Route deviations/diversions? - happens every 30 seconds in a glider.
VRP's?
PAN/Maday calls - not a huge relevance
Class D airspace ? Don't want to fly in it anyway.
etc etc
And then I was supposed to sit in a box and talk my way through an entire power flight (and I'd never flown power in my life)
And isn't there some issue about having a PPL medical to qualify for the RT licence? Not sure if thats true,but I head a rumour.
So I bottled out and remain legally confined to the gliding channels only, despite having a full ICOM in the glider.
Things could be made easier! (but don't worry chaps, by the time EASA has finished with us, there won't be glider in the sky - and not much else either!).