Ceesnapete and Flaps62.
Just to clarify that all Worldwide crew are all experienced crew apart from some Temp crew but most of them have left or moved to Mixed Fleet. In fact experience as referred to in the JPM is just six months !!! so not really something that requires a Worldwide CSD to manage!! Of course on Mixed Fleet they will need to look at this carefully on each flight.
Just like our pilot community, BA has always been seniority led as are many airlines. In fact I would say, that many would say, that the seniority driven factor is actually more of a problem in the pilot community than in our own! Depending of course if you are at the top or the bottom of the list!!!It is usually a problem when you are at the bottom but by the time you reach the middle!! You don't want the system to change !!
I can see however that it will need to change in our community but for other reasons than mentioned by other posters. As both WW and E/F are shrinking fleets and will have no new entrants joining in the future, the same crew will now remain at the bottom of the list forever!! This will mean that some crew will be condemned to get last choice forever and of course that would be unfair!!
These are all my own views