Let's see if he wins anymore slams this year, because he hasn't had a multiple-slam year since 2011

These are supposed to be his prime years....
If they again put Murray, Nishikori, Wawrinka in Djokovic's half as at rigged USO'14 then it will be difficult.
But if they e.g. put Wawrinka and Nishikori in his half but Murray in Fedal's like at the last AO, he would be a clear favourite again.
Even better, let's put Djokovic and Federer together at AO'16 and USO'15 as was always the case during Peakerer's 2008-2011 and Nadal, Wawrinka, Murray in other half at HC slam.
I know it is impossibility 'cause Wawrinka can only play Fedal at Wimb and RG, whereas HC Stanimal is reserved at AO/USO only for Djokovic since 2012, while Federer is reserved for Nadal's half at AO/USO 'cause he is no HC Peakerer anymore and Nike, Kia, TVs, Slams etc. want one of Fedal in the finals.
So, the difference between Fedal's prime years and Djokovic'prime years is that Fedal are still awarded the easiest slam draws possible as when they were no.1 and Djokovic despite being no.1 the most difficult ones as their biggest rival, no matter RG,W,USO.