The problem for carriers on the cargo side is the difficulty 'signalling' to each other, in (near) real time.
If I understood my passage colleagues correctly, the fact that scheds, fares etc show in various retail outlets means that competitors can monitor each other quite closely.
If carrier 'A' sets out a fares package for a specific city-pair then competitor 'B' can react to this if so desired; e.g. 'B' might reduce its own fares package to compete, or, if really annoyed massively discount below the levels of 'A', and if really, really annoyed massively discount all city-pairs for which 'A' is a competitor.
'A' then knows that toes have been tread upon
On the cargo side pricing is quite sticky, with contracts at levels that cannt be changed except at xx days notice ((only when change is upward of course)) and there is no real signalling mechanism
Hence the very public statements by the big carriers - only by announcing it to the market in a highly visible way can 'A' signal 'B' and keep it all above board & legal
Of course I've been out of it for 8 years & I expect this is all total rubbish, so I'll go back to
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