If you're talking about squaring off the sides, like is evident in the poster above me's picture, then no it wouldn't look dumb. I had it done for the first time when I got my hair cut a couple weeks ago.I asked my drag dad why they did it and he's like dude...that's what they do with guy's hair.
But if you mean shaving the hairline higher to create a higher looking forehead or something then yes, it would look incredibly retarded.