Actually, we made the world's first true twin, the 1260, a completely symmetrical ski.  This was only the case for the first two years when the ski what white/sidewall construction and orange DJ sidewall construction.
For next year we are re-introducing a true twin tip with the invader, 110-83-110, centered stance, totally symmetrical ski.
And also, yeah we own the patent, but no we don't enforce it.  We don't want to hold back skiing's progression.  I freely encourage all ski companies to make equal height tip and tail skis.
Jordan Judd
Product & Promotions Manager
Line Skis