This is in two parts:
While living in Huntington Beach, Ca. I met a very lovely young lady hitting against the wall one day and of course without hesitation, asked if she wanted to hit. She did and we did ... So immediately I discovered she had very good technique in ball control with reasonable pace and shot select. We weren't playing a match but during a moment when we sat for some water, I told her of my assessment of her game off the ground. We played this game called 21.
It's merely a ground stroke game where you don't serve. Someone starts the point off with an underhand delivery that has to be beyond the service line. From there, game on. your objective is to win the point in anyway you can. We were toe to toe, I'd win a point, she'd win a point. Ok here's my point, based upon ground strokes only, she was equal to what I gave her. I have a fairly big first & second serve and placement has always been a weapon for me. If we were playing a match, I doubt she would have faired well against my serve but taking that out of the mix, she had a good chance of winning.
If you look at some of the biggest hitters on the WTA and matched them up against an ATP player, you would still need to drop down pretty far in the rankings before it would be an equal match because men have the upper body strength that even the best hitters can't match.
Would Serena do well against say James Blake? No I doubt it. But would you need to grab someone below 1000 for her to do well? I doubt that as well. Why would a guy be in the 500's or below 100 in the World if you contend there's very little between the top and bottom?
Next question: There are many celebrated Coaches out there who have helped many of the top players in the world but all things are not equal. What a coach achieves with one player does not mean he will achieve with another. It's what that player brings to the table. Not everyone is destined to be a Nadal or Federer no matter how hard they work. There's an unknown factor in all players that cap their overall results. Some guys will never win a major no matter how hard they try. They can even have an occasional win over say Federer or Nadal but when it comes to the majors, the Champions rise to another level that most players just can't do.
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