Hi D Mc,
I have a Fatman, given to me by a friend who could never get it to hook at all, especially on medium conditions. He said it was only a "high-priced spare ball". But I have always maintained that ball designers don't necessarily make bad equipment; it is usually operator error that causes failure with a particular piece. Mine was left in that same 11:00/5:00 configuration, with only spotty results at best. Sometimes it hooked, most times not. I put it down in the basement. That was 2yrs ago. Pulled it out recently to shoot spares with, and guess what....it still is a good spare ball. However, had it redrilled in a stacked config...kinda 1:00/5:00, with both pins on the right side of the centerline, and the darn thing hooks now. I do have to use slow speed however, like 13-14mph, but it will hook! It is even better on dry conditions than the mediums...smooth and continuous. Also, I have developed a little more hand since those days as well, but I have re-added it to my arsenal.
Hope this helps.