^I particulary don't see anything wrong with that either, I just like the artists to take some time to record a "live" vocal track before doing it.
But I do prefer when the performers find other solutions to the dancing/singing version... Being it having back-up singers/backtrack (the most usual) or doing a Beyoncè and openly not singing nor miming while dancing.
Or the cooler solution:
"Look! No microphone!" :V