Is there such thing as a perfectly drilled ball though? Maybe at pro tour level, but there are so many variables to take into account...unless you have money to burn and a dozen test balls at your disposal. You can drill a ball up to do a certain thing, fine tune the reaction with balance holes and coverstock adjustments...but the result is not always what you expect. I drilled a rico Brunswick Karma for a good player a few weeks ago to give him a nice smooth even reaction for something fresh...then the ball went off its head. I just looked at him and said "sorry mate, it shouldnt have done that" He loves the ball though and has since thrown 300 with it. Sometimes even the unexpected can be good in a bowling ball.