They showed that episode again over the holidays, all great TV and so on, but if you pay attention at the end, the co-ordinates on the satnav shows latitude 78 deg.
Wikipedia's write-up says that they reached the Magnetic North Pole, which is very close to the true/geographic North Pole (which has latitude 90 deg, obviously).
Not true, they had reached the Geomagnetic North Pole, which as the map in the previous link shows is hundreds of miles further south. They set off from Resolute, which has latitude 74 deg, which is to the north of the geomagnetic North Pole, so on the outward journey they were heading south (or south-east or south-west or whatever).
So AFAICS, epic fail.
