The problem with Chikezie is that he seems to be trying on multiple personalities like outfits - one may stick if it seems to fit. He was complimented on the bluegrass outfit he wore last week at the beginning of his song, so he donned it again this week. Then in the middle, he tried on a Taylor Hicks outfit, even imitating some of Taylor's vocal style when he whipped out the harmonica.
I found it disturbing that he added the harmonica to the performance. Just because you can blow into one and make a series of notes come out does not mean that it takes no effort or time to become proficient. He used it as an accessory to his outfit, rather than as a real musical instrument.
And, for those who really listen to bluegrass, he is not a bluegrass singer, just someone trying on the outfit.