I don't think it's a particularly good harmony and the sound mix is bad which doesn't help as the harmony is too loud

LK and JD's voices worked most effectively together when Luke Kelly sang the melody and Ronnie Drew sang the chorus an octave below.

Great video nonetheless for an old Dubliner's fan and I'm enjoying looking at some of the others from the links. I always liked the original line up better than some of the later combinations so this one is a rare gem.

Chris