The Real Story of Abba explains that while "experiments in applying classical music to a pop format were very much in vogue at the time [Intermezzo No.1] ha[s] come to seem a little dated".
Wikipedia píše:Der Tagesspiegel says the song, "in contrast to the catchy masterpiece [Mamma Mia]" that it was coupled with on the single, "has a rather psychedelic-disturbing character"