Is it possible to separate the singer from the song? Technically perhaps,
but in reality no. A Bernstein performance is an experience.  A Stokowski
performance is an experience.  This is because they, like any great
musician, studied those black marks on white paper and interpreted them
as a result.  They were singing a song they believed in and one they felt.
While I may disagree with their singing, they make the song what it is as
a result.  At the same time, some singers merely are going through the
motions, kind of like karaoke.  Listen to Bernstein's or Stokowski's
Mahler, then listen to the other ilk.  You will hear what I mean.

Peace,
bob stumpf