actually, your edge under foot puts the most force into your turn. don't get me wrong, the tip and tail help, but being that your edge under foot is stationary to your boot, and the tips and tail flex, of course most of the power comes from under foot. that is why it is almost COMPLETELY NECESSARY to wear the skis on opposite feet for park riding and carving. when you slide rails you dull your inside edge a lot more than your outside edge, and that's no good because if you understand the physics of skiing at all then you know that when you carve a turn the majority of your force comes from the inside edge of your downhill ski. so if you wear your skis on the same feet everyday in the park, your outside edges are gonna be waaaay sharper, so if you swtich the skis for carving, it will be your INSIDE edge that is sharper.
and of course a park ski WILL NOT carve as good as an all-mountain or racing ski, but you can still lay down some tracks if you know what you're doing...
sorry for the rant, enjoy your day
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