^ Can you imagine how awkward evolution would be:
WHOA YES WHOA YES WHOA WHOA YES YES YES.
'nough said. xD
Well, I think the fillers work, our singing voice is what a chirp is to a bird. It's just an instrument, and it should be used. Not really empty.
Plus the ad libbing for B&D is so~ catchy.
People just find whatever they can to complain about Ayu imo. xD