I think you could well be right. It wouldn't surprise me if he wins every Grand Slam event this year, subject of course to injuries. I think there's every likelyhood this year that each of the semi finals will be Djokovic beating Murray, and Nadal beating Federer, with Djokovic beating Nadal in the final. The current rankings are Djokovic 1, Nadal 2, Federer 3, and Murray 4. So the way the Grand slam events drawers are made results in the semi finals most likely being 1 against 4 and 2 against 3. Although Murray could beat either Nadal or Federer, it's not so likely that he will get to meet either. Although Federer is a great player, he is the oldest of the 4 which is why I think Nadal is more likely to get to the final.
On a point of trivia, Djokovic is exactly 1 week younger than Murray.