Well yeah. It's less clear whether the Giants worked any miracles with Ruf, or if it was more the three years in Asia. Other than their judicious use of him, which the Phillies haven't really had the luxury of doing with their older players this season with all the injuries (and failed youngsters).
Is Ruf actually a better defender than Hoskins or is he just able to play RF and LF on a limited basis?
I'm always skeptical when people think a new hitting coach can fix a player (or a team); I think what that article shows is, this can actually happen, but it's about the organization, not any specific coach. Of course the Giants are also exhibit A for that with regards to the manager.