Bobby, i rate Emerson the 3rd or 4th player of the 60s, clearly behind Laver and Rosewall, but behind none other. I know, all this is speculative, because Emmos faced the pros only since 1968. Maybe Gonzalez did sporadically better, maybe Gimeno on ability was on equal terms. But i think, that Emmo in the 60s was more consistent than Gonzalez, who had long spells of inactivity, and did better in big matches than Gimeno.
Rex Bellamy wrote that Emerson is both overrated and underrated, and he is imo right. Yes, he wouldn't never have won 12 majors with all the pros competing, yes, his high ranking by some experts like Hopman and by most polls isn't correct (in behalf of Rosewall or Gonzalez).
But this is certainly not Emmo's fault, who was and is one of the niecest and warmest people in the whole tennis world. He certainly was no bum, but one of the most athletic and mental solid players ever, who had sound allround game for all surfaces, a great backhand, a great serve and volley game, and excelled in the fith set. Newcombe made an all time list of Australian players and ranked Emmo third, behind Laver and Rosewall but ahead of Sedgman and Hoad. Of course, this is debatable. But Emmos record in Davis Cup, in majors, in singles and doubles and in hth really stands out. His major wins include wins over Laver, Newcombe, Stolle, Roche and Ashe, his 1964 season was one of the best amateur seasons of all time. He has a big lead in hth over Newcombe, who could barely beat him in the 1970 Wim quarter, when he came through Stan Smith and gave Newk his toughest fight there. He still beat Ashe in 1974 in the Aetna World Cup, when he was 36. Much is made of his 5 set defeat by Gonzalez at RG 1968, i even had to deal with some, who stated, that he lost all pro matches to the older Gonzalez. But he did hammer Rosewall on clay early in spring in Florida 1968, had a string of pro wins over Nr. 1 Laver in 68, and in 1970 stopped Gonzalez in the Classic Series in their most lucrative match, and was still Nr. 6 or 7 on the Money winner list.