Laying out recessed lighting in perfect grids is something that people tend to do because it provides more even illumination in a multi-use room and looks nicer when staring at the ceiling. However, for specific task areas put the recessed lighting where you need it. People don't stare at the ceiling. They walk into a room and look at your stuff. When well lit they may love the feel of the room but not notice how this was done. It is important that the light not glare at you which negatively attracts your attention to it. Even professional interior designers can get hung up on laying out lights in grids. That's why there are professional _lighting_ designers.