JMO but some don't have spinners to adjust at home. Some may think the ball is at it's best at OOB. Some may just "go blindly in the night' with whatever the company says.
Hard to say. One thing I do not think most folks realize, oil. What may well be medium in one house may well be med/heavy, and so on. So what one person says here or on other sites they take as fact, for them it may well be but for another house/style it just doesn't add up.
What makes me think this was chitown and his Dooms. Here, I did what he did, didn't work on much over medium oil. Maybe slightly over at times because on Sundays we followed a PBA League, so some nights it was fine others, depending on what thier shot was, it just didn't.
I'm not saying he was not factual, shoot, he's forgot more about covers than most of us will ever learn, just that at one house it may well be different at another.
IMO, there's more to the cover grit than most want to deal with. Locally, last season, I adjusted covers on balls that the owners wanted to sell and get a new one. Why ? nothing more than it needed to be at a different grit. Once that was done they were happier than when they first got the ball.
So, IMO, the cover makes more to reaction than most want to believe.
Maybe, again, JMO.
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az guy aka: R & L Bowlers Pro
rlbowlerspro@cox.net