Regardless of whether or not CW lip-synch; to do lip synching *WELL*
does require considerable talent; AND if captured to video a talented editor.

Now if the performance is billed "Live" then, I'd expect it to be live. But Then, do you eliminate *all* backing tracks? If on a CD someone doubles a voice, do you drop it for live performance or use a pre-recorded track to give the same effect? Or hire additional talent?

Same for instrumentalists; what do you do when the same performer plays several instruments on a cut? Or multiple tracks on the same cut?