https://www.youtube.com/watch?v=92cwKCU8Z5c
While looking for a live performance of this amazing song I come to find that this particular song was never sang live, so I did a little digging to find out why.
According to an expert, this piece was a real technical song with 3 octave range and almost impossible to do live.
But, that seems very vague for the most famous pop group at its time not the sing one of their best songs live ever, don't you think?
He continues, this kind of song needed layering with harmonies and over dubs, so there's no way it could have been done live as it would have taken all the emotional over turns out of it.
Ah! so that's it. As I can remember this song was written basically as a farewell letter from Bjorn to Agnetha, this, since they were going through a divorce!
So putting two and two together, they could never do this live at the time because they could never reach that same emotion as in the recording.