I think he keeps the OBP around .350, and with his power, a .450 SLG% is not out of the question. Look at Adam Dunn's career arc. He has several seasons of very much below average BABIP, but plus .850 OPS's. Now that doesn't mean Napoli equals an in-his prime Dunn, but they are similar hitters, and Napoli actually makes more consistent contact.