I love this group 5 stars

For the audience's ability to hear a song done in the manner they are familiar hearing, yes. After all, what does it matter anyway? The group who recorded the song is still singing it only they are singing it along with their own recording which they made in the first place.

Yes! They are singing, and having to work their butts off, too, because the sound quality is not that good and they are having to almost shout the song. When they lip sync, they also sing, but they sing with their recording being played which is louder and better modulated to studio quality. The audience can hear it better, one reason they do it.

nah, they broke up years ago