New Fleet operating separately from the EF/WW fleets is essential to realise efficiencies. Otherwise, New Fleet will be hamstrung by legacy inefficiencies.
I can't help but wonder whether BASSA have got BA to exactly where it wants to be. As soon as New Fleet gets to a reasonable size, BASSA (if it still exists) will have to start playing ball with the company to avoid crew being starved of work. Something of a "win win" for BA.
It is almost tragic that whilst BASSA has been throwing its toys out if the pram over imposition, two of the most fundamental changes to crew (pensions and New Fleet) are going ahead with no input from crew and agreement with BASSA.