I think in all games it's a combination of both, honestly. You can just 'brute force' your way through many games, but mostly you won't. You'll manouvre, you'll trick and trap and use guile - all of which are down to the player's skill. And you'll use everything your character has, so there's plenty of that, too
Even in Diablo it's about far more than just how fast you can click the mouse button.
