The fine art of singing background vocals is a rarely noted craft.  Had a session last night with the legendary Tommy Lepson and Dusty Rose and it was something of a lesson in this arcane art.  Listening to them find the EXACT phrasing in the lead vocal track, and then discussing whether to match it or straighten out the rhythm in order to more fully feature the lead was intensely interesting. I can sing and I have had to put down bg vox on Chaise Lounge recordings.  I struggle with this. I struggle with matching pitches, phrasings and vibratos.  It was nice to have some old-school guys in the studio who come by those skills via years of singing and a high degree of natural talent.