Dude, are you serious? I'm only posting once and i'm not trying to pick a fight or anything, but your drawing is simply retarded and is going against what you're saying.
1. a moment ski at say, a 180, would be the same length and a rounded-tip ski in a 180... which does not correspond to your drawing, and goes against your statement which i'm quoting.
2. if you were to put those drawing on top of each-other and compare (as stated above), the moment skis would definately show with a greater girth than that of the rounded tips.
3. i don't even know what to think, because your logic is rediculously skewed.
I do believe you are incorrect.
Cheers, mate.