How does this make sense? It only helps if they want to reposition 76s elsewhere in the system, not the existing 772s. By older 777s do you mean some of the very old ones with the older engines? I've read somewhere (I think on the AC forum) that some are on the market, but I cannot imagine CO adding a different 772 configuration to the fleet, especially not in GUM. What types of routes would you expect to see??

ETA: I just read the .nut thread and still don't see it making a lot of sense.