Originally Posted by timnz
The OP is completely right. The Federer Nadal head to head is completely and utterly about the surfaces they have played on.
Federer is better on Clay (his worst) than Nadal is indoor (his worst)... hence, in the 2000's Federer made far more finals on clay - and who did he meet in those Finals? Nadal of course (because it is his best surface). Unfortunately indoor tennis has moved from being one of the most important surfaces in the 80's and 90's to almost non-existent now - that also contributes to Federer and Nadal lack of matches against each other on that surface.
I always say to those who think Surface is irrelevant to head to head - Really? Do you think that Borg/McEnroe head to head would be the same if they had played all their matches on clay?
The problem is Fed played Nadal on his favorite surface(FO) but Nadal doesn't play Fed on his favorite surface(USO). Fed made 6 straight USO finals, there's no Nadal. However, Fed made 5 FO finals and Nadal was there. Not only the disparity of the surfaces they've met, but the difference in the age. They are 5 years apart, peak at different times and decline at different time. It would make sense to compare if both player are at the same age. And even if they are at the same age, the surface discrepancy would skewed the h2h. So we have two fallacies when comparing their h2h:
1. Disparity in age
2. Disparity surface