About this whole discussion of using a backing track or not, I like Megadeth's approach to it (questions and answers with Kiko Loureiro, around 3:30:
https://www.youtube.com/watch?v=OiOVu93pTFo&t =7s)
He basically says that they don't have any backing tracks of instruments that they have on stage. They don't have extra guitars, extra acoustic guitars, any backing vocals, drums or percussion. If they can play or sing, they do it live, but they do use orchestrations. Songs like 'Trust' have orchestrations, so they use backing tracks there. If the songs have intros, like 'Dystopia', 'The Threat is Real', so they have backing tracks for those intros.
He adds that the band, however, uses click track, so they can play in sync with videos and other elements of the show, and that songs with orchestrations, extra instruments or intros need the backing tracks to create the atmosphere like on the album.
I know DT sound evolved, but if you hear Live at the Marquee, their more raw live sound was great back then. And this "Megadeth approach" is basically what DT did until 2010, just without the click track - and DT could just add that IMO.
It's only a matter of preference, I do still think DT is amazing live and I'm really looking foward to see them in Rock in Rio!!
