If performers can't bring something new to a song ,something that expresses the spirit that went into the songs composition ,they should leave it alone . I used to think The Holy Ground had been nearly murdered by countless drunken renditions until I heard a young woman singing it in a bar, slowly and gracefully ,without the shouted Fine girl ye Are chorus.
Television adverts are the worst killers of songs . The First Time Ever I saw Your Face could survive Top of the Pops but not the British Gas ad. May it rest in peace