If you remember Carrie did that a couple of times on Idol, and Paula Abdul asked her, how can you do that. And Carrie said she didn't realize she did. That is how natural it is for Carrie.
IKR?! I grabbed my stopwatch to count yesterday! I can do that ending part of this performance somewhat easily which makes me proud cuz' I used to have bad breath control and would lose my breath in bad places like when I sing You Belong With Me by Taylor Swift and now I can hold a note for around 30 seconds!
Maybe the Botox affected her vocals.. If Botox, is supposed to help somebody with a muscle disorder and it screws them up imagine what it does to your vocals!!!