What's interesting for me is that someone as strong and fit as Nadal uses a racquet with a swingweight of 355; Paes, a doubles player, uses a swingweight of 351.
I'm pretty sure that's indicative that 5.0-5.5 amateurs in general, who don't train like professionals, and amateur singles players shouldn't use swingweights higher than, I would say, at most 340. If you're rated any lower than that, using something higher than 330 is completely counterproductive to achieving better results, improving stroke patterns, and maintaining the energy to move and play your best.
It's true that having a heavier swingweighted racquet helps you hit a heavier ball if you swing with the same speed and fundamentally sound pattern that you employ with a lighter swingweighted racquet, BUT THERE'S A POINT AT WHICH ADDED SWINGWEIGHT IS HARMFUL TO ONE'S GAME. That's to say nothing about the effect swinging such a heavy swingweighted racquet has on your fitness and movement.
Although I'm convinced by some of the more knowledgeable posters on this board that the swingweight measurement itself is imprecise and that there are, in fact, multiple types of swingweight, I still think the measurement has real world, on the court relevance.
Repeating myself, but in conslusion: I understand and agree with the argument that higher swingweight frames may allow you to use less effort to hit the ball harder, heavier, etc. But this argument completely ignores the fitness realities that constrain EVERY tennis player. If you want easier power, try lower tensions, a different string, or a racquet with a bigger sweetspot that has a swingweight suited to you.
