My skepticism is of people saying "the reason he made mistakes in his SP is because of injury". He's been a very consistent jumper in the past, but his jumping ability is diminished from the past... so it makes sense for him to make errors. Note his mistakes in his programs at Russian nationals. Note that he didn't attempt the 4T internationally in his SP last season when he had no problem attempting it before.
And he's had more recent problems with his 3Z than in the past. It would be like me saying "Chan must have been injured at Worlds because he's been able to land 3Z's in his sleep when he's healthy enough." to rationalize his poor performance. I agree that injuries may have contributed to a poorer performance, but I can't picture him wanting to compete while injured and further risking injury, against such a strong field that could push him off the podium and likely would have, and in a competition that isn't particularly important which he's won many times before.