The precipitous rise in the level of professional tennis can be attributed most conveniently, to the influx of 'technology'. The utility of such a loose and ubiquitous descriptive term is that it encompasses everything that we want it to - new coaching machines, training methods, healthier nutrition and above all, better equipment.
Better equipment is a debate with almost no chance at neutrality. Over the past 20 years, the average athlete's physicality has changed significantly. I simply cannot bring myself to believe that Borg was as fit as Nadal. And even if one argues that he was and I accept your argument, I can still further support myself by claiming that the Monfils, Ferrers and Verdascos of the Seventies merit no comparison to their counterparts today.
This is where equipment plays its role.
A racket is crucial enough to warrant consideration because it is the biggest overall variable factor that determines the balance of the game. If tennis comes down to a game where the player who hits the ball hardest wins, it will inevitably die.
Power tennis is undoubtedly exciting but there is a Catch-22 situation that accompanies it. If the points become too long over an extended period of time, the sport becomes boring. And if they remain short (think Sampras at Wimbledon), then tennis loses its fine balance of sweat, elegance and attrition.
No modern ATP player exemplifies the impact of technology as much as Rafael Nadal. In fact, it is far easier to believe that Nadal is a product of his own generation rather than the other way round. This doesn't appear to be the case with Federer.
Imagine Federer with a wooden racket or the T2000 metal stick that Connors popularized—He would, in all likeliness, still be as fluid, artful and graceful to watch. Less effective? Certainly. But only because of the expected decrease in spin and power that would accompany the switch.
Somehow, Nadal does not fit into this vintage picture of Federer in white pants and a wooden racket.
Making him play with a wooden shaft would be disrespecting the game that we have come to identify him with. For one, his open shouldered stance would generate little power and end up falling well short of the base line. The bounce that he generates with that motion-defying topspin uppercut forehand of his would be relatively minimal.
Even his two handed backhand (which appears to be as risk-free a shot as there is), would be affected. This is because when Nadal swings on the backhand, he doesn't appear to hit through the line in one fluid linear motion as the textbook advises. Rather, he tends to improvise on the spot, muscling the ball through wherever he wants it to go.
His open shouldered stance is as technically flawed as one can get. The only successful players that avail of it are ones who have been coached personally, i.e. by a family member. Apart from Nadal, the Williams sisters have employed this technique to the most devastating affect.
Conventional wisdom assumes that at the split second moment when racket strikes ball, your upper and lower body have to be in a state of momentary balance with the torso imparting momentum to the shot by leaning slightly forward. The reason why Nadal and the Williams sisters have been so successful is more easily explained not by the rightness of their technique but rather by the self (and externally instilled) mental belief that they can execute the stroke coupled with countless of practice hours of actually doing so.
The unorthodoxy of this style of play is one that requires forgiveness. Your racket has to be forgiving of the nuances that can accompany the imbalance of the shot and the irregularity in the motion of the swing. This is not to take away anything from Nadal or his like but simply to claim that modern racket technology coupled with the improved physique and fitness of the average tennis pro have successfully maximized its effectiveness to a large effect.
Today's top of the line rackets are best sold by rocket science-like explanations. While titanium is still popular, it is no longer the selling point as it was when it first breached the market at the turn of the century. A modern racket may have an eclectic and complicated combination of carbon fibers, glass fibers and thermoplastic filaments such as nylon, epoxy resins, as well as other exotic metallic alloys.
The Head Liquidmetal model range, developed at the California Institute of Technology supposedly imparts more power and momentum to the ball due to the amorphous state of its atomic structure. Gimmicky? Sure, but what player wants to take the chance of seeing his competitor with an external advantage?
Wilson modeled its latest line along the existence of the "K-Factor," which combined various fibers in specific directions so as to maximize the hitting spot and provide extra control. Prince chose the "larger-holes-in-the-frame" tactic as its USP and changed its stringing patterns to seemingly make its rackets more forgiving.
Micromanaging the legality of materials is an exercise that is futile at best and horribly inconvenient. It is akin to performance-enhancing drugs in the sense that the moment it is discovered (which would be difficult to do), another one would perhaps already be in the pipeline.
The detractors that raise the point of both players having the same advantage are overlooking this simple fact: While rackets may not have a ceiling, the human body does. A Roddick serve at 150 miles per hour requires a reaction time of approximately 0.3 of a second. A good 10-15 miles faster and it would be physically impossible to bring the racket down in time.
Watching a flurry of aces is entertaining but not when it extends beyond a game and supersedes the beauty of a modern tennis rally.
And just as Federer is a unique and prodigious talent, so is Nadal. But they are different kinds of talents, each one as effective in their own way—one maybe a bit more than the other. Furthermore, they are in no way representative of this generation of tennis.
That responsibility is shouldered by the average tennis professional ranked in the top 100 or 200 that never grabs the limelight and yet still has the ability to amaze the knowledgeable spectator watching him play. You couldn't say this a couple of decades ago.
Tennis has come a long way and its rise in quality has been near meteoric but there maybe a threshold somewhere down the line which should never be crossed for fear of redundancy.
The problem is that we don't quite know how far we are from it.