Djokovic beat peak Big4 to win slams and tons of yec/masters, not Roddick and Hewitt.
Djokovic didn't beat peak "prime" Fed any time in slams, let alone peak fed.
AO 08 fed was mono fed and after AO 10, fed was not even prime fed.
Murray's best 2 years in slams were in 12-13 and djokovic went 2-2 vs him in that period.
even old fed was beating up Murray in 15 (wim and cincy)
obviously dominated Murray in slams before that as well. 5-1 overall (USO 08, AO 10, Wim 12, AO 14, Wim 15). Murray's only slam win coming in AO 13 in 5 sets after ~31.5 year old fed was exhausted from a 5-setter vs tsonga the round before.
Djokovic did win 3 in a row vs nadal in 11-early 12, but then lost 4 in a row after that.
Meanwhile while Djokovic in his prime years in 14-16 was busy going 1-3 vs Stan in slams, old Fed went 3-1 vs Stan in 14-17 in slams.
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in his prime, Fed was also beating nadal (06/07 Wim), Djokovic (07/08/09) Djokovic, Agassi (04/05).
Saying he was only beating Roddick and Hewitt is like saying Djokovic was only beating Nishikori, Cilic and Raonic in 14-16.