I know Christiaan I was the one who originaly raised it back on page 1.
It would undoubtably be expensive, the mil managed it with 243 & 243.1 but then that was UHF. Personaly I don't think it would become the new chat freq, most CAT/GAT listen out on 121.5 not to keep upto date with the footie but to be in a position to help others and to be helped. Many have benifitted from that over the years. A-lot of CAT operators require it as SOP too. Most people therefore listen out on it for good reason and as we generaly only listen to 2 box's selecting a practise freq would not appear high on anyones list. If someone does want to chat freight train is on 123.4 and it would be just as easy to switch to that as to a practise freq.
So that leaves us with trying to stop people misusing 121.5 be they CAT or GAT. How do we do that ? I made some suggestions earlier so just wondered what you thought. Mariners tend to have the same snag with channel 16 so maybe its just insoluble but surly with a group of professionals that cannot be true ?
As an aside CAT abuse of 121.5 is always going to be more noticable as it tends to occur at 30 something thousand feet and has a large footprint. Equaly its CAT who hear it all for the same reason.