Bull. Djoko would have beaten Fed more easily than Murray did and it wouldn't have affected his perf in the final. (Djoko has already won AO after beating Fed in the semi and Murray in the final in 2011). He also had Murray, Nadal back to back in 2012 and I can't think of any tougher combination (much tougher than Fed + Murray), although the other way around (Nadal first and Murray next) would no doubt be even worse. It doesn't matter what draw you throw at Djoko at AO, a bit like Rafa at RG although not for as long.
Fed would have beaten Djokovic in the final in 4 sets.