This is not BA bashing. Could have been any carrier. Accident investigations more often than not reveal not one single cause but a series of contributory factors. The very fact that this thread exists is because, by following company SOPs, what the crew believed to be a relatively safe operation (as so many of you go to great pains to point out) was compromised as they found themselves facing additional problems as the flight progressed. It all ended well but, let's be honest, not according to the SOP script. Don't let SOPs fool you into complacency. They're not infallible.