Good teams in the NBA have what we call "depth." Having more than one talented player at a position is a huge benefit as long as both players' skillsets complement each other. On the other hand, having two talented players at the same position with redundant skillsets is what we call a cluster-you-know-what. With Lance Stephenson and Gerald Henderson, the Hornets will be hoping for the former. But we will have to wait until the season to see if they can actually play together.
The first stop in answering this question was MySynergySports.com, which is a wonderful resource, which confirmed that Stephenson is just better at practically everything on offense. Even Henderson's advantage in points per possession (PPP) on transition plays last season could be attributed to Steve Clifford's system more than as an advantage as a player. In fact, Henderson could carve a niche for himself coming off of screens while Stephenson isolates, a situation in which he was a top-50 player. Turnovers could be a problem, however, but I think that's a casualty you can live with as far as Stephenson goes since he will usually make up for them in a variety of ways. If Stephenson can maintain an assist percentage over 20 percent, the Hornets will be a better team for it.
This could work the same way in rebounding. Stephenson definitely posted better rebounding figures last season, but he was being asked to follow his or his opponent's shot, whereas Henderson was told to get out in transition. One isn't any more right than the other; it seems both players are capable of adapting to different styles.
Defensively is where the two players really show separation. While they both allowed similar PPP overall last season, they did it in different ways. Henderson was better in one-on-one situations like isolation and pick and rolls. Meanwhile, Stephenson thrived stifling opponents on hand-offs, cuts and spot-up plays. This is looking more and more like depth. While Stephenson is more "Anything you can do, I can do better" offensively, each player has different strengths and weaknesses on the defensive end. Because of this, Charlotte can throw more of Stephenson or Henderson at an opponent depending on the matchup.
This, my friends, is what we call depth. It appears that both players offer varying strengths which should be enough for them to complement each other. The Hornets sought to upgrade the shooting guard position and appear to have done just that. It's likely that coming off of the bench is ideal for Henderson, and if he can continue to give the team his current level of production the team will be better for it. But if Clifford calls both onto the floor at the same time, it appears they can coexist on the floor. For this reason, I wouldn't consider trading Henderson. It's a long season and having two capable players at the weakest position in the league is a huge benefit to the Hornets.