I would guess that if BALPA comes out against Willie Walsh that his position might actually be strengthened, since significant shareholders are, as I stated earlier, generally only interested in profit and share price and, certainly in relation to the former, Walsh is probably seen as having done well (so far).
On another matter, terminal capacity/crowding, I wonder whether Terminal 5 might not end up being one of the most crowded at LHR. I haven't looked closely at the numbers, but I understand that T5 is built for 30 million pax per annum, with BA already carrying around 22 million (not sure whether this includes the Spanish and Australian routes to be consolidated at T3). This doesn't leave much capacity for future growth. Will the new incumbents at T1 and T4, for example, be able to offer passengers less crowded terminals?