I disagree with most of your analogy, but the ball itself is not what you are calling it. There are quite a few "Tour" balls that can easily be compressed for amateurs with slower swing speeds. Things have changed with the golf ball and your assumptions were true 5 years ago but not now. The B330RX and the Srixon Z-star are both "tour" balls but geared for people with average swing speeds (85-90) and can quite easily be compressed. As for your analogy with the piano. Your analogy works if you are talking about what kind of equipment beginners should by, but has no bearing at all in regards to fitting. Should a brand new golfer spend $500 on a driver? They dont need to. Similar to the piano. But any piano player beginner or advanced wants their piano tuned appropriately. That works well as the analogy for fitting.