In my naive younger years, when Blu-Ray was being announced, I thought, "Hey, they could put the dialogue on one track, the music on another, and the foley business somewhere else, then you could mix those as you needed." Just put the baby down? Switch to dialogue, with only ten percent explosions and soundtrack.
(This of course would only be useful where you had original audio tracks)
(This of course would only be useful where you had original audio tracks)