I rarely introduce movie canon into a question, but I'm watching Goblet of Fire and there's the scene where Moody/Crouch Jr is helping Harry figure out how to solve the first task (dragons), where he says, "Krum's head may be filled with sawdust, but Karkaroff's is not; you can bet he's got a plan."
Is there a basis in canon that Viktor Krum's head is "filled with sawdust", i.e. he's kind of dopey? Or is this just a characterization choice used in the movie? I didn't get the vibe off Viktor in canon that he's a "dumb jock" or not a talented wizard. So what gives about Viktor Krum? Is he daft or is he a smart and capable wizard who happens to be the best Quidditch Seeker in the world?