Ariana Grande proved two things while performing impressions on Jimmy Fallon. First, the girl can sing. Second, Christina Aguilera is a ridiculous performer. For years I’ve said she sings as if she always has something to prove, moving away from the melody in favor of exhausting vocal acrobatics, to the deficit of the song. Yes, Aguilera is a talented singer, but she gets in her own way. Watch as Grande showed us all why pulling back might be a better option.