Brickguy,
I think you may have misread my meaning in my quote you re-posted. When I look at a customer's previously drilled equipment there are many signs that point to an improper fit. Seeing these things, explaining to the customer on what should be corrected and how the grip will be affected was what I was trying to point out. Therefore, making a previously bad fitting drilled ball a very useful tool in building a new grip. Very rarely do I see grips that can't be improved upon. In my area, many operators utilize a "cookie cutter type of drilling" and just copy someone else's work. Having been a victim of these guys for years, was one of the reasons I decided to get into this. I can relate to your experiences of throwing money at the pro shop. Understanding The span/pitch relationship, as compared to what each individual bowler's hand is capable of doing, is the science and art of fitting/drilling their ball. Believe or not, you wouldn't have had spend $500 in my shop to get a better fitting grip.
You are aware of the limitations involving the fitting ball, while others reading this post aren't. These limitations have to be taken into account when using it. A skilled proshop operator won't just really on one fitting tool to put the best possible grip into a ball. I was echoing Pinbuster's post of it's proper use and I did say it was a good tool to have. However, just owning one doesn't make you a good ball driller.