I understand what you are saying, but these guys swings are built to be the most accurate when going left to right. The only time you will see Belmo playing up the outside is when there is some blend to allow the ball to start reading early. Most of these patterns don't have much volume outside of 5, so you can play straight and the ball will feed to the pocket. The US Open pattern has 50+ units of oil all the way across, so if you play up it, you better be perfect.
Some players can go straight up the lane, but they have to be very soft with their hands and have amazing angles through the front part of the lane. Guys like Mika, Voss, Duke, Walter, are the few off the top of my head that can do this.
Again I will draw your attention the angle of entry. If most of those guys go up the lane on something that long and flat, the ball will enter the pocket so steep they will never carry. I bowled the US Open in 2006, and I can assure you that there was absolutely NO shot outside of 8 all week.
The small X Factor to this is the topography of the lane. The lane surface itself has a touch of "memory" built into it that creates a (VERY) small amount of recovery to the right. By "recovery" I mean you can get a shot back that is maybe....MAYBE 1 board right of target down the lane. If you move to the right you give that up, as their balls tend to have more axis rotation and tilt, and it won't read that going up it.
I can completely understand where you're coming from, and I wish you could have seen Mike Fagan in match play throw a sanded Gamebreaker up 5 and had absolutely nothing. He would miss the head pin...go through the face...leave a 2/10...stuff a 4 pin. There was just no look out there and he was throwing an aggressive resin ball.
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