Visionary usually makes reference to the MB and anti MB somewhere on there site.

Back in the day the mb use to be located above the pin. MB Pin then cg. I've seen two different patterns where they flip the ball.

One is for a ball with a 0-1" pin and less then 2ozs top weight.  The pin is placed above the bridge with the cg stacked above it and the fingers drilled deep to get the proper weight for the ball.

The second is for a 4" pin or longer. The pin is placed at least 1.5"s below the thumb with the cg just above the thumb. The fingers are drilled shallow and the thumb drilled rather deep for proper weight. When you draw a line from the bowlers PAP to the Pin it should be at least 1.5"s below the thumb to prevent it from flaring the thumb. Which is the reason you need the longer pin placement. This ball takes the flare away from the fingers and brings it down to the thumb. Giving the ball more forward roll and less angle off the drier boards.
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