I don't propose to be any sort of expert here, but having followed the progress of this situation since the beginning, I would say that BA's grand strategy might be along the following lines:
a. Allow OpenSkies to grow to the point where a requirement to feed connecting passengers from short-haul European routes onto long-haul transatlantic flights ex-London no longer exists, enjoying all the cost-saving benefits that will provide the company.
b. Subsequent reduction of required short-haul capacity, thereby freeing up large numbers of slots at LHR / LGW which can be used by BA themselves for other long-haul routes (more profitable than short-haul), or alternatively sold, leased or rented to other members of Oneworld Alliance to generate cost-free revenue, whilst simultaneously transferring some of the risk of competitive transatlantic flights to other airlines.
c. Finally, further into the future, eventual transfer of operations ex-London to Openskies, now BALPA have given up their right to strike on this issue. (Is this time-limited, or has a de facto precendent been set now, by the way?)
And there you have it: in the long-term, a complete outflanking of the BA pilot body, at least as far as the transatlantic routes go, replacing it with crews from a cheaper cost base (OpenSkies), and having already removed a good proportion of the mch less profitable short-haul feeder routes into London, the whole game guarantees significant profits for BA in the medium-to-long run.
To conclude, I am very sorry Balpa managed to get themselves stuck here between a rock and a hard place, and I am somewhat concerned as to how this will impact the pilot body as a European whole.
This might be a day we all live to regret.
All a bit depressing really...