Stu put it well.
the shovels of the Made'ns are wide and soft enough to keep you afloat even if you mount forward. The forward mount reduces the swing weight of these giant sticks greatly, which as Stu pointed out, makes spinning easier and the ski is more nimble.
The soft tail is another important point. As the Made'n tails are basically just as soft as the tips, altough I've never skied any mounted at 0, I'd assume the tails would wash out really easily. I find that with the forward mount, the extra tail actually makes the skis a bit more stable.
Anyway, I've skied Made'ns as several mount points and pesonally found that in my opinion, +4 is ideal if it's being used as mainly a pow ski. I'd go +5 or +6 if it's park/pow ski...that's where my 179s were and they were fun as hell, but just too short on most days.
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