McEnroe has 7 slams, Borg has 11..Thats a big difference; but if you have to compare 14 to 16, its not much, and other factors would come into picture..
Fact is H2H means NOTHING. If Nadal is truly the superior player, then he should be able to surpass Federer's records. If he can't, then clearly Roger was the more dominant/superior player when considering playing against the ATP as a whole which is what you're made of. Winning tournaments means something, not beating one player.