got this book
love it
love it
Pick up Multi-Platinum Pro Tools by Nathan Adam/Brady Barnett - they go in depth about editing techniques.
The tip he's referring to is hard quantizing/auto-tuning background vocals and editting main performance to grid.
Again, as Egan stated... it's NOT AT ALL about getting bad performances sync'd up - it's about achieving a polished, 'perfect' sound that the genre/times demand. Again, pick up that book. There's a philosophy behind editing that essentially takes a great performance and makes it over-the-top. The same techniques we use to make shitty bands sound decent or even good (autotuning, quantizing) can be utilized to make an already great band the very best they possibly can sound.
this all, of course, leaves out the 'natural is better' argument - we won't get into that.