I agree and was about to mention the backing track. It doesn't have the same
sound effect as it would have if there was a live band.
I finally watched the NHK interview - thank you for posting Spiral- and it was nice to see this side of Namie. With celebrities, they each have an image and the public will form judgements based off them. This is especially true in Namie's case. (people always perceived her as "cold") But from watching this interview she is more relatable to me, for example how she aways doubted herself and her reasons of not doing a MC. I've always had the same thoughts about MCs, how it seems so hard to have to come up with different things to talk about all the time. I always wondered how singers did that. It's just nice to know Namie's personality is closer to mine than I would imagine.
Also, Ken's cover of WMWM sounded exactly as I had imagined it would

Need to see it in full.