One last thought... I wonder after the IFSD, with the flight planners help, the re-plan (fuel calculation) suggested they could make it to Heathrow direct.
In amongst a minefield of speculation or worse, I seem to recall that somewhere a long time back in this thread, the mention was made of an adverse Flight level change while crossing the Atlantic that changed the plan and the fuel parameters. If that's the case, then it looks to me like the original plan probably would have been OK.
In passing, and it's completely off thread in one respect, there was an interesting and reasonably accurate if somewhat sensationalist program on RTE this evening, french made, talking about aircraft accidents and incidents.
One fact that emerged was that in a particular year, probably 2 to 3 ago, as Air France were still flying Concorde at the time, and they were talking about engine failures during take off, and the ability of even large twins to still get airborne, there were 18 Million take offs, and 200 "problems" after V1 that did not result in any form of subsequent "incident", other than a safe landing. It was mentioned in the same section of the programme that "incidents" occurred on average every 2000 takeoffs on aircraft such as Constellations, which changed with the arrival of jets, and now, with the modern jets, the "incident" rate is down to less than 1 per million take offs.
I suspect that in the absence of spotters with radios, this "incident" might not have even reached this board. That it has, and is provoking such heated comments is slightly worrying, not because it made it here, but because it's generating such heated emotions. Given some of the other emotions that get generated over other subjects, I'm just glad it wasn't an Airbus that had the problem, we'd be at risk of an eternal thread!