Lets be quite clear that the crew were not instructed to go anywhere. BA do not instruct crews on where to go when an aircraft has a technical problem. They will inform crew what the best options are in terms of ground handling, technical support and alternative arrangements for passengers, but the decision on the ultimate destination for the aircraft rests solely with the flight crew. This is not some third world airline where the pilots are monkeys flying the plane who will unthinkingly do what the management tell them for fear of losing their jobs.
There was no 'HOMITIS' here. The crew spent the night assessing every en-route airfield for its availabilty and calculating and recalculating three engine fuel burn as well as two engine drift down altitude and cruise performance. At any stage of the process they could have diverted to an en-route alternate. At every stage of the process across the Atlantic the criteria for continuing were met.
Once (yet!) again, the 747 is approved by Boeing, the FAA and the CAA for flight on three engines. The CAA have no problems with the conduct of the flight. The mayday was a seperate issue which the entire UK 747 flight crew community have learned from. The plan was sound from the outset and the CAA agree with that. As the CAA, not the FAA, regulate UK flight operations the continuation policy will remain. The only thing that might change is that we'll have to avoid US airspace in order to avoid the FAA scoring cheap points trying to promote their own industry.