Not in every case. Imagine using something like Photoshop with nothing but keyboard commands. I've got a graphic designer friend who's spent probably a third of his life on Photoshop, and he swears by a hybrid technique -- one hand on the mouse for drawing, the other on the keyboard for switching tools and doing menu command shortcuts.

GUIs are great, keyboard interfaces are great, but sometimes one's just better suited for the task than the other.

'course, I'm still waiting for thought-controlled computers...

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I'm too sexy for my .sig.