Because they're shaking up the story of this game, so why not?
IT's very likely just wishful thinking, but I'm really sick of the same stories in Zelda games. Granted Skyward Sword's story looks like the best version of it yet, but like... why can't they do something different
- protagonist as Zelda or Ganondorf to focus on THEIR triforce pieces (Zelda's game could be more mentally challenging, Ganondorf's game could be far more action-oriented)
- keep around the triforce pieces but show us a time when their role involved three entirely new people and what they did to change Hyrule in their own small way, perhaps give the triforce of courage to king of hyrule, triforce of power to a powerful gerudo lady, and triforce of wisdom to a sheikah and let us see how that story unfolds
-make a console Zelda that expands on the idea of Zelda and Link working together as a team, make it a co-op online game similar to Portal 2 where a puzzle needs to be solved together, Zelda can use her sheikah magic to manipulate time and space whereas Link is more about his items/combat