I think that Seattle got screwed but even I wouldn't have overturned this call. Using whatever standard they have, this wasn't clear and convincing evidence that they got it wrong the first time. Now, here is the place where it gets interesting, if they had ruled that this WASN'T a TD then the replays would not have been evidence to overturn that ruling either. So, did the refs have the idea that the just 'expected' the Steelers to win and whenever something close happened they just 'presumed' that it was okay? You will never prove it in a million years, but it certainly is more speculative than the 2000 elections and there are still millions of people wearing tin hats after that one.
Their 'two-minute drill' was over in 10 seconds.