This has been a great thread. Everyone has made good points. Rudy Jramillo, I believe teaches what Diablo speaks of: The pure rotational swing. Where as Dave Hudgins teaches: To Implement the hands in a linear path with rotation.
They are both considered two of the best hitting instructors on the planet, simple as it gets. As powertoallfields said: We are both right to an extent. Just as you have different styles of hitters, the same can be said with coaching techniques.
As instructors it is our job to adapt rotation and hand path to each individaul hitter as needed to make him a better player, this will not be the same for every player, nor should it be.