it's simple math..if less than 5% of pro's are using it then obviously it has no place in the PRO modern game.
I will only say that all it says is that it's not in the modern game by and large, not that there isn't a place for it.
At any rate, people assume that Roger "needed" to move to the '97 just because he did so. Yet, that's just faulty logic. What does make more sense, and is probably more likely true, is that once Babolat sales soared due to the early successes of Nadal and Roddick, every manufacturer was envious and sought to copy that success. As the larger racquets became more and more mainstream, due to the popularity of the afore mentioned pros and subsequent sponsorship of more pros, the mids haven't proven to be inferior regarding performance capability, but simply less popular. The success of Fed and Sampras prove otherwise. I use these two not because their names get levied about here so often as "proof" but rather Sampras played during a time when multiple pros have claimed that the game was faster back then and Fed continued to have success as the game became slower. In other words, faster or slower, mids can handle the pro level game just fine.
Getting Fed to use a '97 simply marries Wilson's Pro Staff brand recognition with consumer popularity thereby helping to ensure the brand's sales success for decades to come. Fed simply legitimizes the changes in the "hearts" of the purists while grabbing the attention of ignorant (I say that not as an insult) coaches who predominantly influence years of juniors as they come up through the ranks. I say ignorant because, having worked the junior scene for awhile now, I can't tell you how many times I overhear words to the effect of "emulate, emulate, emulate" as THE reasons needed to achieve success.
Academy kids are great examples of this and it's amazing how many of them plateau to the college level at best. Nadal isn't where he is because of his strokes, it's because of his tenacity, something that is largely undertaught (again, just from my own limited experience) as the crucial factor for success as opposed to "stroke production". Fed is the same way. Nole, finally, appears to have embraced this and success has followed whereas before he treated losing as defeat and acted like a clown. Ferrer is another great example.
I daresay that the fact that Fed has continued to be as successful with the '97 only serves to subtly prove that head size is largely irrelevant. I fully expect that 95 will be extinct eventually too, in favor of 100. This says nothing about the prowess of 95 racquets to "compete" on tour. It says everything about hype and popularity. Basically, all the reasons many here say aren't good reasons to buy racquets, are EXACTLY the reasons most people buy racquets, including juniors. Why do you think paintjobs are so prevalent?