+1,000,000,000Guess the other reason is to break the outline and give it a pivot point but it's a twin, and has plenty of built in pivot.
The next level is hold w/ the speed of a twin. If a board is too loose, then you can't drive off the bottom or through turns b/c you're busy nursing turns.Reason most people like twins is the loose feeling, but if you pair it with a narrow pin tail, you kinda loose that advantage.
Like the outline of my CI Twin Pin much better and it holds fine in bigger surf with no wing.