airage,
I agree that there are lots of advantages to GB in being part of the BA brand - lots more advantages than disadvantages. Load factors on every GB route jumped by about 25% after they were designated by BA flight numbers. Serious money for the company. But GB does pay BA the fees - when the going is good (like now) or bad (e.g. mainline cabin crew strikes a few years ago which affected GB bookings by 50%). BA needs cash cows at the moment.
There is plenty of future for the BA brand in europe with its decent seat pitch, reliability, customer service etc. providing the ticket price is not perceived as a rip-off.