You may be confusing the word "lite" in this fight diet. A Lightheavy who moved down to Middleweight versus a Lightweight who moved up to welterweight. Napoles is just too small, plus, Hopkins possible punch-punch-butt technique will find Jose's fragile eyebrows (cuts).
I agree, Hopkins would be just too big. I'd see it somewhat similar to the De La Hoya fight but Napoles would be a little more willing to mix it up (not good for him).
Hopkins was a big middleweight and Napoles was a small welterweight, plus Napoles' edge in slickness is only slight here, prime B-Hop is just too big, too strong, too rough, and too skilled himself for Napoles to win. Hopkins stops Napoles in the 10th.