I'm having some trouble understanding this one. I was trying to see how one might use it to create a cube like the one in the exercise at the end of Mesh Modeling Fundamentals. After you enable a mirror modifier, do you actually have to enable clipping and pull additional cubes out of the original with translate before you can start sculpting details that will show up on all four corners? I just got out a single basic cube and tried to bevel one edge with the mirror modifier enabled and all axes checked, thinking this would bevel all edges at once, but it doesn't seem to work this way.