federerfanatic, claycourt players don't have long primes? They last as long as any. Kuerten was tough for more than 5 years,
Kuerten's 97 French Open win was a huge fluke in hindsight, at that point in time. He wasnt a top player at all in 97 and 98 outside of that win and was unseeded by the time he defended his French Open title in 98 even with the benefit of the points of his 97 French Open title. That says something about the rest of his results in 97 and 98. Remember the top 16 then were seeded, he did so little anywhere else even with points from the previous years French Open title he still couldnt rank in the top 16 by the 98 French Open. Kuerten's prime was definitely only 99-2001, a 3 years prime. His 97 French Open win was a hugely premature out of nowhere type thing, similar to Sampras's 1990 U.S Open win, although Sampras was atleast a top player in 91 and 92 he too was clearly not in his prime yet.
and would still be if it wasn't for injuries.
Debateable and will never be proven. Also even though he is a clay courter he doesnt play a "grinding" style either, so doesnt even really fall into that category.
Agassi made finals nearly a decade apart, winning one of them.
Agassi game is to grind his opponents down, totally different. It is not to be grinded, while counterpunching the way Nadal, Corretja, Wilander, Chang, all are. Plus how many years in a row was Agassi ever at his best. His career was stop and go, a year or two there, a year or two there.
Courier was also competitive for a long time.
Courier had only a 3 year prime at best, 91-93. By 94 he was already a shadow of his old self and fell out of the top 10 by years end, only to very briefly appear at the bottom of the top 10 again before falling out for good.
Corretja had a 5 year prime probably, 97-2001. Not too bad but not that long. Players like Sampras, Becker, Edberg, probably Federer will have much longer primes then that, closer to a whole decade.
Again not too bad as longevity goes, but still retired at 25. Plus while he was a grinder he did not rely on it as much as many of those others. He had a much stronger serve, he could volley much more effectively, he could hit the ball earlier with more raquet speed even with the wooden raquets then these more prototypical "grinders" do with a graphite.