You could, but you wouldn't be making a point. I won't begin to disagree that stud pitchers help win championships, because that's obvious. But your argument that one is necessary doesn't fly in my book. In just the examples you cite...Cole Hamels had a 3.72 FIP in 2008, and Chris Carpenter made one start in 2006 (Wainwright was the "ace" with a 3.90 FIP).
The Braves have two pitchers this year whose FIP numbers were lower than those (Hudson and Beachy). Pitching depth can get a team to the playoffs just as easily as a top-heavy rotation headlined by a dominant ace...and once you get to the playoffs, it's pretty much a crapshoot anyway.