Proper fit is critical for overall comfort and performance, and though a professional fit can greatly improve both of these, there is no one-size-fits-all formula. It can take years of riding and occasional adjustments until you find what you think is the perfect fit. I had been riding for some 15 years, and thought I had finally gotten my bike set up right, then an old coach recommended that I change my seat position slightly. The change felt awkward at first, but it made large difference in my performance. I guess that is why teams hire coaches.

It is a good idea to experiment with different adjustments, because even when you think you have found the perfect fit, you still might be able to improve it.