Why change where Humphrey plays? He looked fantastic as a cornerback. The team already has two top safeties and he hasn't showed any bad traits so far in a game as far as his coverage ability. I mean it is a back up plan to possibly move him but the idea of having two towers that are shutdown with him and J. Smith gets me so excited for the season.
I think it's because a lot of people hyped him as a potential SS, and that notion has some legs, he shows amazing SS traits, but as many have pointed out his absolute best trait is how well he uses the sideline, so while he could be a very exciting SS his ceiling is a shutdown boundary corner.
You rarely see corners with his aggression and physicality, he's a bully, like a freak athlete version of talib, and he is scheme versatile showing great press ability along with incredible recognition and awareness to come downhill to break up plays when he's playing off or zone, that downhill style is another safety trait, but safeties have to play more horizontal, and Humphrey is prone to slip ups and the less you expose him to that the better he should be, and safeties don't get to jam dudes into the bleachers. He shows great safety traits but with some refinement he has top 5 cb ability