Of course Duke had scoring droughts. You know who else had scoring droughts? Every other team in college basketball. That includes teams such as Kentucky or UNC. (Do you remember the end of the first Carolina game when their offense was so impotent they didn't get a shot off in the last 3+ minutes?) Maybe you didn't watch any of the games that featured any-of-the-other-teams-in-Division-I. Maybe you didn't watch what happened during our games when the other team had the ball. Which seems likely enough, since you think offense is what held Duke back last season. If you had, you would see that all teams go dry for long spells. Random chance basically guarantees it.
In any event, to say that Duke used isolation ball a lot or assisted on a low percentage of baskets says nothing about the potency of the offense. Sure, it describes the offense, it explains how we went about trying to score, but it offers no insight into whether we were actually good at scoring. And the truth is that Duke was very good at putting up points last season. I don't see how this is even an argument. Even with the weak offensive production we got in the ACC tournament and NCAAs with Kelly out, our offense was the 11th most efficient in nation last year. At times it was #1.
Duke stumbled at the end of the season. I don't think anybody denies that. The loss of Kelly surely played a role there. The collapse of Dawkins's confidence surely played a role. Playing two elite defenses in UNC and FSU surely played a role. Lady Fortune very likely played a role. It's unfortunate that we hit a lull at the worst possible time, but we did. It doesn't change the fact that our offense was the team's strength for the lion's share of the season.
As for the loss of Rivers, let's have some perspective. After 2011, Duke lost the #1 pick, the #21 pick, and a second round pick to the NBA. We came back this past season and put together an elite offense. Rivers is expected to go mid-first round. Given that much lesser loss, I see nothing to prevent K assembling a similarly excellent offense--albeit one that functions differently--with next year's plethora of talent.