Mobile phones in aircraft? Whatever next!
I am now waiting for a police speeding ticket due to my wife leaving her phone (registered in my name) switched on all the way to Greece a couple of weeks back - in a B737. When she landed, to her horror, she had text messages welcoming her to Switzerland and a couple of other countries on route. Oops!
BTW, I thought that folks used 121.5 for chat, giving the Captain's welcome passenger chat etc (BA out of EGCC really had bad finger trouble that day; it went on for about 2 minutes, we got the full works).
Seriously though. If a formation wants to talk to each other, they could adopt the military procedures. e.g. Use a relevant formation callsign such as the lead aircraft's registration plus "Combine", nominate a leader and brief properly. The latter is an ANO requirement anyway. Leader only does the r/t, giving details of each individual aircraft to ATC as required.
Call number 2 across to the next ATC freq. by transmitting, for example, "G-ABCD combine, 123.4, 123.4 - GO!" Number 2 ought to find this no great surprise if the trip has been properly briefed with regard to diversion airfields etc. Use London Info for longer legs away from airfields, or use the nearest field for Flight Information where available. And obviously keep the chat to the minimum, no nattering on someone's frequency, keep that for the bar.
You might feel a bit self-conscious but it works.