neither should a tattoo smack in the middle of your forehead have any effect on your competence, but professionalism, yes. You could act sort of way and dress any way you'd like, that has no bearing on your competence, but how you are viewed professionally? That is exactly how we are judged, like it or not. Professional decorum. Would you want a clown walking into your room saying they are performing your surgery today? Would your grandmother, mother, or grandfather? Why not just save your personal expression for outside the workplace. Your workplace is a place of WORK, not self-expression.