How the hell can you not feel a difference between center and -7.5cm?? That is a fucking huge difference between where the midsole of your boot is mounted and the center of the sidecut & flex of the ski.
The only time it really makes sense to center mount your bindings is when your ski is symmetrical in sidecut, camber, and flex. Mounting it anything but center will feel funny- you will be off the sidecut, off the center of the camber or have uneven amounts of camber or uneven amounts of rocker, and the flex of the ski will be unbalanced.
If your ski is not symmetrical and you mount it in the center, it will be just as unbalanced- you will be off the sidecut, off the intended camber/rocker profile, and the flex will be a bit off depending how far off center is from the designed recommended mounting point. If the ski was designed to be ridden off-center, what actual benefit is there to mounting it center? If anything you are making the ski ride funny and it will not help you ride switch better.
I'm all for center mounting a ski, just do it to the appropriate ski so you can maximize the design and intended purpose of the ski.
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