This specific Chinook situation could perhaps even be handled with an "inter-pilot" transmission on the FIS frequency? Though I must say I have yet to come across a real occurrence of interpilot transmission.
Regarding
Personally nothing would wind me up more than the need to keep chatting to other pilots in the air.
: I totally concur - and this is exactly why I think a dedicated chatter frequency would be a good thing. I hear too much chatter for my liking on my local FIS frequency - even if I realise it must be worse elsewhere.