I continue to believe that at the beginning of the open era it was hugely important, and thus an important factor. That does not mean that I think it is the most important factor, Bobby.
Well, I'm not sure either, Bobby, because I don't have data, and I'm never going to get it. I do know from studying statistics very carefully over the last 25 years or so that the advantage is always with the guy with the stronger service game when stats are otherwise equal.
By this I mean that if two players are winning the same % of games, overall, but one player is holding serve more easily, the better server generally has a statistically better record winning matches.
This leads to what I call "the Sampras effect", which I have been puzzling over for at least a couple years now.
What this means is that players like Sampras and to a slightly lesser degree Federer appear to have an extra gear. My hunch is that very powerful servers coast when they are ahead a break, saving energy and only going all out on return when things get even, or when they fall behind. In contrast, players like Agassi, Nadal and Murray had/have to keep the gas on more uniformly because they are more likely to be broken. This does not, by the way, particularly apply to Nadal at his peak on clay. In spite of not having a dominant serve, he had a very dominant service game on clay.
I don't have stats on Rosewall, so I'm guessing, and I may be 100% wrong. But just looking at his serve I would think that he must have been more vulnerable to being broken, and that even Laver was probably a good deal more vulnerable to losing serve than Gonzalez.
Over the last 25 years or so there has been no one I can think of with a phenomenally high % of holding serve who has been much under 6 foot, and even then the really tall guys have at least a slight advantage over Sampras, Roddick and Federer. But the giants all have relative weaknesses in returning (Karlovic, Isner, Raonic) and so none of them are at the top of winning games both on serve and return.
I just have a lot of trouble imagining a man Rosewall's height and with the serve we see in videos winning service games as easily as the other guys with bigger serves. I would say the same thing to some extent about Laver, but as I remember Laver had a very powerful serve for a shorter player.
Again, we don't have data. If my hunch is right, Rosewall would have had an amazingly high rate of breaking serve. At his peak he would have been close to Nadal on clay, but of course on fast surfaces, which would have meant he would always be a threat to break back after being broken.
I'm repeating that I have zero data to back this up.
This is what I do have, although I may still have minor errors, which I'm always looking to correct:
Going back all the way to '68 I see that the players who were most dominant in winning games in slams are Borg, Nadal and Vilas, but this is on clay. Game dominance is highest on slow courts, lowest on fast courts, so in general this dominance shows up highest on clay, lowest on grass, and somewhere in the middle on HCs.
When I eliminate all slams not on grass, the guys at the top of the list are interesting because this catches most of the great ones. Rosewall does very well on this list, for all games.
To some extent I think that looking at only the last three matches - usually quarter final, final and championship match - might be even more important. McEnroe is at that top, two years in a row. To me that is significant. The next names are Federer, Sampras, Borg, Connors. Rosewall is next. However, the players who do best on this list also usually won grass slams several times, so more chances to have a dominant slam. Laver does not fare so well because his 1969 grand slam was extremely tight, a real miracle in terms of a story, and he did not contest as many times after that on grass slams.
As you can see, I have part of the story, but in order to find out what I'm missing I would have to go through match after match and calculate not only how many games were won and lost but also how many breaks there were. That's beyond my patience.
You unfortunately don't always recognize those of us who are ALMOST as enthusiastic as you are about Rosewall. I've always been a huge admirer of Rosewall and remain so. Remember, I am utterly uninterested in GOAT debates.
