So you think every one-hander before current era was worse than todays? Best one-handed backhands are from previous eras, but speculating their success against Nadal´s forehand is rather pointless, since Nadal´s heavy spin is made possible by todays equipment, and previous eras didn´t face that kind of shots.
As for Corretja, he was way past his prime by the time he played Nadal.
No, I dont think every one hander in previous era is worse than today's, when did I say that? I said there are better one handers around than Corretja's in this era and yes, they need to deal with 3000 rpm jumping over your shoulder, raquets which produce more spin than they ever did before.
Yes, Corretja was past his peak when he beat Nadal, Costa wasnt really far from his peak so he cant have this excuse losing to a 16 year old Nadal. I think Costa, Corretja and Kuerten clearly had the best onehanded backhands in the late 90s claycourts and the little evidence we have is that a 16 year old Nadal was already causing them trouble.
Kuerten had a magnificent backhand but poor movement, he used to push everyone around on claycourts but against Nadal he would lose the point as soon as Nadal gets a grip of the point with his forehand, I dont think Kuerten would be able to turn defense to offense against Nadal, I dont think Nadal would be a very good matchup for him at all, which would be sad because I really was a fan of Guga, not of Nadal's tennis.