Do you think Mika Nakashima's live performances are better than her recorded singles?

Have you listened to her latest single: Over Load? The single is composed of great catchy songs and the video's also spectacular. I just wonder why her latest single just peaked at #8 position....but after I watched her live performances in Music Fighter and the like, I realized that her live performance of the song isn't that great. <In my opinion, her live performances caused her sales to be just satisfactory...> Isn't it that live performances are also promotions for singles/albums.