You don't think Nadal never having a losing record against all his main rivals is relevant?
Generally
no (
see red text below), but especially when compared to the metrics considered most important and by which tennis players have (and can) been measured across the ages - such as majors won, weeks at #1, season ending championships etc. He has won so much more than most players who have beaten him that it's irrelevant. And so the case is between Federer and Nadal.
H2hs are not even a blip on the radar when you compile a body of work on a player to line them up against tennis players across the ages. They never were until literally 5 years ago when Nadal fans started seeking something to show their favourite player was better than someone who was clearly the higher achiever.
But, since some are so intent on using the h2h argument I'll frame it another way: what is a bigger blight on a player's career - a player losing to a #50 in the second round of a tournament and thereby protecting their h2h versus their key rivals
or a player losing to the #2 or 3 ranked player in a final and having their h2h negatively affected?
A partisan viewer will say "protect the head to head" - but look at the flips side: how on earth is that a better mark on someone's record than the player who lost in a final? I mean, seriously - that is some major moron level logic in play there.
Chris Guccione, Xavier Malisse, Mikhail Youzhny, Nicolas Mahut, Juan Monaco, Carlos Moya, Joachim Johansson are the sort of people Nadal was losing to - a group of players Federer has never lost to. He has 45-0 record against that
entire group and Nadal lost to
all of them in less than two seasons. In those two seasons Federer won 6 majors (the equivalent of Beckers or Edberg's
entire careers) and Nadal won 2 - but Nadal still had a 6-5 winning record over Federer. So, who was the greater player in those two seasons? Federer or Nadal?
Taken in complete isolation the h2h does show something for sure - such as a player having a mental or skill advantage over another. But this can be quite independent to overall ability which the Federer vs Murray situation is a perfect example of. No-one in their right mind would chose to have Murray's achievements over Federer's because Murray heads the h2h.
Similarly, when you compare Federer and Nadal, it would take a very partisan person to suggest that the period when Nadal was often losing to players who Federer then spanked when he won a title is NOT a huge flashing neon light indication that Federer was,
by far, the greater player (in that period - the sort of 2006-2009 period).
Apart from Davydenko, and that's 5-6, who else is there? Federer has losing head-to-heads against Nadal and Murray, two of his biggest rivals, which includes 8 losses in majors to his biggest rival, Nadal.
He yet has more of the achievements that are considered most important than both of them
combined. That is what matters more. Until Nadal hits 17 majors he's simply not a remotely credible GOAT candidate - he is second, third (or lower) on every major metric by which tennis players are compared - while Federer is #1 on many of them, by miles in some cases too.
Nadal has won a career Grand Slam and a record number of masters series titles. His winning percentages are excellent, and beyond ridiculous on clay.
No doubting that at all. But, comparing percentages while he is his prime with someone clearly well past their prime or long since retired is pretty amateur level stuff when it comes to argument credibility. Compare like for like.
(Re: first comment: Should Nadal get to 17 majors then the head to head does become a factor worthy of considering more - but only then. A situation such as Edberg and Becker is perhaps a good previous example. They're even on majors - Edberg is well ahead in weeks at #1, but Becker has whopping 25-10 lead in the h2h, including their last 7 encounters and both Davis Cup matches)