Interesting call on Ali Stealer. His 1970's figures were 30 fights for 27 wins and 3 losses. The losses being: 1971 vs Frazier I - UD pts. 1973 vs Norton - SD pts. 1978 vs Spinks - SD pts. Ali's figures form start of 1975 - end of 1979 were 12 fights for only the 1 loss (Spinks as above). For mine it's Monzon, Ali, Duran.
He had some real questionable decisions though, and was fortunate to have kept on to the crown until 1978. He was badly faded by the latter half of the 70s as his age and beatings (especially Manila) had taken its toll. Duran was dominant from 1972 until the end of the decade, with the one loss being very decisively avenged, and was around his peak in the mid to late 70s. Monzon reigned for roughly seven years as the MW champion and was around his peak for his reign as well.
Muhammad Ali is my favourite boxer of all time. I have to be fair here,though. Ali is definitely in contention for greatest boxer of 70's from his output circa 1970-75. Because he's older than Duran and Monzon,he naturally faded from 1976-78,while Duran and Monzon were still prime during the latter part of the decade. My man Ali is third best of the 70's pound for pound with Duran just shading Monzon for first place.
It's Duran then Monzon 51/49, Ali got it due 2 his high profile as heavyweight, even Angello Dundee said Duran should have got it & it was Duran's misfortune too be around when ali was:yep praise indeed:smoke