Remember,Duran skipped Jr Welterweight or he would have won titles in 5 different weight classes.
And it was Duran who went up 12lbs to beat SRL.Do you really believe that SRL could go up 12 lbs and beat Roberto Duran at his natural weight?
And Duran was more past his prime than SRL when he went up in weight classes to win his titles.
You can't go head to head because Duran was alot more past his prime in the 3rd fight than Leonard was.
Plus Duran was the greatest light weight of all-time!