To much trouble, you would still have to log on to each FIR unit. A better way is ACARS, but again it's hastle and has a lag people will just reach for 121.5 instead as its faster. Maybe mandating ACARS for all ground handling calls would be good to stop the number of acidental 121.5 calls and inevatible backlash from everyone on the frequency or a more robust way of delivering frequency changes. For example contact London control on Bravo Foxtrot and then you decode your self. One of the main problems especially over Spain are ATC loop errors, they give you a frequency, you read it back incorrectly but they don't pick that up and then the cycle of lost coms starts! Happens every 10 seconds in Spain...